document_title: Berlin Blockade

question_text: what was the purpose of the berlin blockade

question_tokens: what was the purpose of the berlin blockade

text: Berlin Blockade

text: Postwar division of Germany[edit]

text: From 17 July to 2 August 1945, the victorious Allies reached the Potsdam Agreement on the fate of postwar Europe, calling for the division of defeated Germany into four temporary occupation zones (thus re-affirming principles laid out earlier by the Yalta Conference). These zones were located roughly around the then-current locations of the allied armies.[7] Also divided into occupation zones, Berlin was located 100 miles (160 km) inside Soviet-controlled eastern Germany. The United States, United Kingdom, and France controlled western portions of the city, while Soviet troops controlled the eastern sector.[7]

text: Soviet zone and the Allies' rights of access to Berlin[edit]

text: In the eastern zone, the Soviet authorities forcibly unified the Communist Party of Germany and Social Democratic Party (SPD) in the Socialist Unity Party ("SED"), claiming at the time that it would not have a Marxist–Leninist or Soviet orientation.[8] The SED leaders then called for the "establishment of an anti-fascist, democratic regime, a parliamentary democratic republic" while the Soviet Military Administration suppressed all other political activities.[9] Factories, equipment, technicians, managers and skilled personnel were removed to the Soviet Union.[10]

text: In a June 1945 meeting, Stalin informed German communist leaders that he expected to slowly undermine the British position within their occupation zone, that the United States would withdraw within a year or two and that nothing would then stand in the way of a united Germany under communist control within the Soviet orbit.[11] Stalin and other leaders told visiting Bulgarian and Yugoslavian delegations in early 1946 that Germany must be both Soviet and communist.[11]

text: A further factor contributing to the Blockade was that there had never been a formal agreement guaranteeing rail and road access to Berlin through the Soviet zone. At the end of the war, western leaders had relied on Soviet goodwill to provide them with access.[12] At that time, the western allies assumed that the Soviets' refusal to grant any cargo access other than one rail line, limited to ten trains per day, was temporary, but the Soviets refused expansion to the various additional routes that were later proposed.[13]

text: The Soviets also granted only three air corridors for access to Berlin from Hamburg, Bückeburg, and Frankfurt.[13] In 1946 the Soviets stopped delivering agricultural goods from their zone in eastern Germany, and the American commander, Lucius D. Clay, responded by stopping shipments of dismantled industries from western Germany to the Soviet Union. In response, the Soviets started a public relations campaign against American policy and began to obstruct the administrative work of all four zones of occupation.

text: Until the blockade began in 1948, the Truman Administration had not decided whether American forces should remain in West Berlin after the establishment of a West German government, planned for 1949.[14]

text: Focus on Berlin and the elections of 1946[edit]

text: Berlin quickly became the focal point of both US and Soviet efforts to re-align Europe to their respective visions. As Soviet Foreign Minister Vyacheslav Molotov noted, "What happens to Berlin, happens to Germany; what happens to Germany, happens to Europe."[15] Berlin had suffered enormous damage; its prewar population of 4.3 million people was reduced to 2.8 million.

text: After harsh treatment, forced emigration, political repression and the particularly hard winter of 1945–1946, Germans in the Soviet-controlled zone were hostile to Soviet endeavours.[11] Local elections in 1946 resulted in a massive anti-communist protest vote, especially in the Soviet sector of Berlin.[11] Berlin's citizens overwhelmingly elected non-Communist members to its city council.

text: Political division[edit]

text: Moves towards a West German state[edit]

text: Meanwhile, to coordinate the economies of the British and United States occupation zones, these were combined on 1 January 1947 into what was referred to as the Bizone[11] (renamed "the Trizone" when France joined on 1 June 1948). After March 1946 the British zonal advisory board (Zonenbeirat) was established, with representatives of the states, the central offices, political parties, trade unions, and consumer organisations. As indicated by its name, the zonal advisory board had no legislative power, but was merely advisory. The Control Commission for Germany – British Element made all decisions with its legislative power. In reaction to the Soviet and British advances, in October 1945 the Office of Military Government, United States (OMGUS) encouraged the states in the US zone to form a co-ordinating body, the so-called Länderrat (council of states), with the power to legislate for the entire US zone. It created its own central bodies (Ausschüsse or joint interstate committees) headed by a secretariat seated in Stuttgart. While the British and Soviet central administrations were allied institutions, these US zone committees were not OMGUS subdivisions, but instead were autonomous bodies of German self-rule under OMGUS supervision.

text: Representatives of these three governments, along with the Benelux nations, met twice in London (London 6-Power Conference) in the first half of 1948 to discuss the future of Germany, going ahead despite Soviet threats to ignore any resulting decisions.[16][17] Eventually the London Agreement on German External Debts, also known as the London Debt Agreement (German: Londoner Schuldenabkommen), was concluded. Under the London Debts Agreement of 1953, the repayable amount was reduced by 50% to about 15 billion marks and stretched out over 30 years, and compared to the fast-growing German economy were of minor impact.[18]

text: In response to the announcement of the first of these meetings, in late January 1948, the Soviets began stopping British and American trains to Berlin to check passenger identities.[19] As outlined in an announcement on 7 March 1948, all of the governments present approved the extension of the Marshall Plan to Germany, finalised the economic merger of the western occupation zones in Germany and agreed upon the establishment of a federal system of government for them.[16][17]

text: After a 9 March meeting between Stalin and his military advisers, a secret memorandum was sent to Molotov on 12 March 1948, outlining a plan to force the policy of the western allies into line with the wishes of the Soviet government by "regulating" access to Berlin.[20] The Allied Control Council (ACC) met for the last time on 20 March 1948, when Vasily Sokolovsky demanded to know the outcome of the London Conference and, on being told by negotiators that they had not yet heard the final results from their governments, he said, "I see no sense in continuing this meeting, and I declare it adjourned."[20]

text: The entire Soviet delegation rose and walked out. Truman later noted, "For most of Germany, this act merely formalized what had been an obvious fact for some time, namely, that the four-power control machinery had become unworkable. For the city of Berlin, however, this was an indication for a major crisis."[21]

text: April Crisis and the Little Air Lift[edit]

text: On 25 March 1948, the Soviets issued orders restricting Western military and passenger traffic between the American, British and French occupation zones and Berlin.[19] These new measures began on 1 April along with an announcement that no cargo could leave Berlin by rail without the permission of the Soviet commander. Each train and truck was to be searched by the Soviet authorities.[19] On 2 April, General Clay ordered a halt to all military trains and required that supplies to the military garrison be transported by air, in what was dubbed the "Little Lift".[19]

text: The Soviets eased their restrictions on Allied military trains on 10 April 1948, but continued periodically to interrupt rail and road traffic during the next 75 days, while the United States continued supplying its military forces by using cargo aircraft.[22] Some 20 flights a day continued through June, building up stocks of food against future Soviet actions,[23] so that by the time the blockade began at the end of June, at least 18 days supply per major food type, and in some types, much more, had been stockpiled that provided time to build up the ensuing airlift.[24]

text: At the same time, Soviet military aircraft began to violate West Berlin airspace and would harass, or what the military called "buzz", flights in and out of West Berlin.[25] On 5 April, a Soviet Air Force Yakovlev Yak-3 fighter collided with a British European Airways Vickers Viking 1B airliner near RAF Gatow airfield, killing all aboard both aircraft. The Gatow air disaster exacerbated tensions between the Soviets and the other allied powers.[26][27][28] Internal Soviet reports in April stated that "Our control and restrictive measures have dealt a strong blow to the prestige of the Americans and British in Germany" and that the Americans have "admitted" that the idea of an airlift would be too expensive.[29]

text: On 9 April, Soviet officials demanded that American military personnel maintaining communication equipment in the Eastern zone must withdraw, thus preventing the use of navigation beacons to mark air routes.[22] On 20 April, the Soviets demanded that all barges obtain clearance before entering the Soviet zone.[30]

text: Currency crisis[edit]

text: Creation of an economically stable western Germany required reform of the unstable Reichsmark German currency introduced after the 1920s German inflation. The Soviets had debased the Reichsmark by excessive printing, resulting in Germans using cigarettes as a de facto currency or for bartering.[31][32] The Soviets opposed western plans for a reform.[31][32] They interpreted this new currency as an unjustified, unilateral decision. They responded by cutting all land links between West Berlin and West Germany. The Soviets believed that the only currency that should be allowed to circulate was the currency that they issued themselves.[33] In February 1948, the Americans and British had proposed to the ACC that a new German currency be created, replacing the over-circulated and devalued Reichsmark. The Soviets refused to accept this proposal, hoping to continue the German recession, in keeping with their policy of a weak Germany.[34]

text: Anticipating the introduction of a new currency by the other countries in the non-Soviet zones, the Soviet Union in May 1948 directed its military to introduce its own new currency and to permit only the Soviet currency to be used in their sector of Berlin, if the other countries brought in a different currency there.[31] On 18 June the United States, Britain and France announced that on 21 June the Deutsche Mark would be introduced, but the Soviets refused to permit its use as legal tender in Berlin.[31] The Allies had already transported 250,000,000 Deutsche marks into the city and it quickly became the standard currency in all four sectors. Against the wishes of the Soviets, the new currency, along with the Marshall Plan that backed it, appeared to have the potential to revitalise Germany. Stalin looked to force the Western nations to abandon Berlin.

text: Start of the Berlin Airlift[edit]

text: Beginning of the Blockade[edit]

text:
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text: The day after the 18 June 1948 announcement of the new Deutsche Mark, Soviet guards halted all passenger trains and traffic on the autobahn to Berlin, delayed Western and German freight shipments and required that all water transport secure special Soviet permission.[31] On 21 June, the day the Deutsche Mark was introduced, the Soviet military halted a United States military supply train to Berlin and sent it back to western Germany.[31] On 22 June, the Soviets announced that they would introduce a new currency in their zone.[35]

text: That same day, a Soviet representative told the other three occupying powers that "We are warning both you and the population of Berlin that we shall apply economic and administrative sanctions that will lead to the circulation in Berlin exclusively of the currency of the Soviet occupation zone."[35] The Soviets launched a massive propaganda campaign condemning Britain, the United States and France by radio, newspaper and loudspeaker.[35] The Soviets conducted well-advertised military maneuvers just outside the city. Rumors of a potential occupation by Soviet troops spread quickly. German communists demonstrated, rioted and attacked pro-West German leaders attending meetings for the municipal government in the Soviet sector.[35]

text: On 24 June, the Soviets severed land and water connections between the non-Soviet zones and Berlin.[35] That same day, they halted all rail and barge traffic in and out of Berlin.[35] The West answered by introducing a counter-blockade, stopping all rail traffic into East Germany from the British and US zones. Over the following months this counter-blockade would have a damaging impact on East Germany, as the drying up of coal and steel shipments seriously hindered industrial development in the Soviet zone.[36][37] On 25 June, the Soviets stopped supplying food to the civilian population in the non-Soviet sectors of Berlin.[35] Motor traffic from Berlin to the western zones was permitted, but this required a 23-kilometer (14.3-mile) detour to a ferry crossing because of alleged "repairs" to a bridge.[35] They also cut off the electricity relied on by Berlin, using their control over the generating plants in the Soviet zone.[32]

text: Surface traffic from non-Soviet zones to Berlin was blockaded, leaving open only the air corridors.[35] The Soviets rejected arguments that the occupation rights in the non-Soviet sectors of Berlin and the use of the supply routes during the previous three years had given Britain, France and the United States a legal claim to use of the highways, tunnels, railroads, and canals. Relying on Soviet goodwill after the war, Britain, France, and the United States had never negotiated an agreement with the Soviets to guarantee these land-based rights of access to Berlin through the Soviet zone.[12]

text: At the time, West Berlin had 36 days' worth of food, and 45 days' worth of coal. Militarily, the Americans and British were greatly outnumbered because of the postwar scaling back of their armies. The United States, like other western countries, had disbanded most of its troops and was largely inferior in the European theatre.[38] The entire United States Army had been reduced to 552,000 men by February 1948.[39] Military forces in the western sectors of Berlin numbered only 8,973 Americans, 7,606 British and 6,100 French.[40] Of the 98,000 American troops in West Germany in March 1948 only 31,000 were combat forces, and only one reserve division was immediately available in the United States.[41] Because of the imbalance, American war plans were based on using hundreds of atomic bombs, but only about 50 Fat Man-specification bombs, the only version then available to the American military, existed in mid-1948. As of March 1948 only 35 "Silverplate" atomic-capable Boeing B-29 Superfortress bombers – just over half of the 65 Silverplate specification B-29 aircraft built through the end of 1947 – and a few trained flight and assembly crews existed. Three B-29 groups arrived in Europe in July and August 1948,[42][nb 1] but the Soviets possibly knew that none were atomic-capable; the first Silverplate bombers arrived in April 1949.[43]

text: Soviet military forces in the Soviet sector that surrounded Berlin totaled 1.5 million.[44] The two United States regiments in Berlin could have provided little resistance against a Soviet attack.[45] General Lucius D. Clay, in charge of the U.S. Occupation Zone in Germany, summed up the reasons for not retreating in a cable to Washington, D.C. on 13 June 1948: "There is no practicability in maintaining our position in Berlin and it must not be evaluated on that basis.... We are convinced that our remaining in Berlin is essential to our prestige in Germany and in Europe. Whether for good or bad, it has become a symbol of the American intent."[46]

text: Believing that Britain, France, and the United States had little option than to acquiesce, the Soviet Military Administration in Germany celebrated the beginning of the blockade.[47] General Clay felt that the Soviets were bluffing about Berlin since they would not want to be viewed as starting a Third World War. He believed that Stalin did not want a war and that Soviet actions were aimed at exerting military and political pressure on the West to obtain concessions, relying on the West's prudence and unwillingness to provoke a war.[40] Commander of United States Air Forces in Europe (USAFE) General Curtis LeMay reportedly favoured an aggressive response to the blockade, in which his B-29s with fighter escort would approach Soviet air bases while ground troops attempted to reach Berlin; Washington vetoed the plan.[43]

text: Decision for an airlift[edit]

text: Although the ground routes had never been negotiated, the same was not true of the air. On 30 November 1945, it had been agreed in writing that there would be three twenty-mile-wide air corridors providing free access to Berlin.[48] Additionally, unlike a force of tanks and trucks, the Soviets could not claim that cargo aircraft were some sort of military threat. In the face of unarmed aircraft refusing to turn around, the only way to enforce the blockade would have been to shoot them down. An airlift would put the Soviet Union in the position of either shooting down unarmed humanitarian aircraft, thus breaking their own agreements, or backing down.

text: The airlift option critically depended on scale and effectiveness. If the supplies could not be flown in fast enough, Soviet help would eventually be needed to prevent starvation. Clay was told to take advice from General LeMay to see if an airlift was possible. Initially taken aback by the inquiry, which was "Can you haul coal?", LeMay replied "We can haul anything."[48]

text: When American forces consulted Britain's Royal Air Force (RAF) about a possible joint airlift, they learned the RAF was already running an airlift in support of British troops in Berlin. General Clay's counterpart, General Sir Brian Robertson, was ready with some concrete numbers. During the Little Lift in April 1948,[19] British Air Commodore Reginald Waite had calculated the resources required to support the entire city.[citation needed]

text: The American military government, based on a minimum daily ration of 1,990 calories (July 1948),[49] set a total of daily supplies needed at 646 tons of flour and wheat, 125 tons of cereal, 64 tons of fat, 109 tons of meat and fish, 180 tons of dehydrated potatoes, 180 tons of sugar, 11 tons of coffee, 19 tons of powdered milk, 5 tons of whole milk for children, 3 tons of fresh yeast for baking, 144 tons of dehydrated vegetables, 38 tons of salt and 10 tons of cheese. In all, 1,534 tons were required each day to sustain the over two million people of Berlin.[48][50] Additionally, for heat and power, 3,475 tons of coal and gasoline were also required daily.[51]

text: Carrying all this in would not be easy. The postwar demobilisation left the US forces in Europe with only two groups[52] of C-47 Skytrain transports (the military version of the Douglas DC-3, which the British called "Dakota"), nominally 96 aircraft, each of which could carry about 3.5 tons of cargo. LeMay believed that "with an all-out effort" of 100 daily round trips these would be able to haul about 300 tons of supplies a day.[53] The RAF was somewhat better prepared, since it had already moved some aircraft into the German area, and they expected to be able to supply about 400 tons a day.

text: This was not nearly enough to move the 5,000 tons a day that would be needed, but these numbers could be increased as new aircraft arrived from the United Kingdom, the United States, and France. The RAF would be relied on to increase its numbers quickly. It could fly additional aircraft in from Britain in a single hop, bringing the RAF fleet to about 150 Dakotas and 40 of the larger Avro Yorks with a 10-ton payload.

text: With this fleet, the British contribution was expected to rise to 750 tons a day in the short term, a month, but even that at the cost of suspending all air traffic except for the airlift to Berlin and Warsaw.[53] For a longer-term operation, the US would have to add additional aircraft as soon as possible, and those would have to be as large as possible while still able to fly into the Berlin airports. Only one aircraft type was suitable, the four-engined C-54 Skymaster and its US Navy equivalent, the R5D, of which the US military had approximately 565, with 268 Air Force and Navy Skymasters in MATS, 168 in the troop carrier groups, and 80 Navy R5Ds in miscellaneous commands. Planners calculated that including C-54s already ordered to Germany and drawing on those flying with civilian carriers, 447 Skymasters could be available for an "extreme emergency."[54]

text: Given the feasibility assessment made by the British, an airlift appeared to be the best course of action. One remaining concern was the population of Berlin. Clay called in Ernst Reuter, the mayor-elect of Berlin, accompanied by his aide, Willy Brandt. Clay told Reuter, "Look, I am ready to try an airlift. I can't guarantee it will work. I am sure that even at its best, people are going to be cold and people are going to be hungry. And if the people of Berlin won't stand that, it will fail. And I don't want to go into this unless I have your assurance that the people will be heavily in approval." Reuter, although sceptical, assured Clay that Berlin would make all the necessary sacrifices and that the Berliners would support his actions.[46]

text: General Albert Wedemeyer, the US Army Chief of Plans and Operations, was in Europe on an inspection tour when the crisis broke out. He had been the commander of the US China-Burma-India Theater in 1944–45 and he had a detailed knowledge of the previously-largest airlift – the World War II American airlift from India over the Hump of the Himalayas to China. His endorsement of the airlift option gave it a major boost.[46] The British and Americans agreed to start a joint operation without delay; the US action was dubbed "Operation Vittles,"[55][nb 2] while the British action was called "Operation Plainfare".[56][nb 3] The Australian contribution to the airlift, begun in September 1948, was designated "Operation Pelican."[57]

text: The British asked Canada to contribute planes and crews. It refused, primarily on the grounds that the operation risked war and Canada had not been consulted.[58]

text: Airlift begins[edit]

text: On 24 June 1948 LeMay appointed Brigadier General Joseph Smith, headquarters commandant for USAFE at Camp Lindsey, as the Provisional Task Force Commander of the airlift. Smith had been chief of staff in LeMay's B-29 command in India during World War II and had no airlift experience.[citation needed] On 25 June 1948 Clay gave the order to launch Operation Vittles. The next day 32 C-47s lifted off for Berlin hauling 80 tons of cargo, including milk, flour, and medicine. The first British aircraft flew on 28 June. At that time, the airlift was expected to last three weeks.[citation needed]

text: On 27 June, Clay cabled William Draper with an estimate of the current situation:

text: I have already arranged for our maximum airlift to start on Monday [June 28]. For a sustained effort, we can use seventy Dakotas [C-47s]. The number which the British can make available is not yet known, although General Robertson is somewhat doubtful of their ability to make this number available. Our two Berlin airports can handle in the neighborhood of fifty additional airplanes per day. These would have to be C-47s, C-54s or planes with similar landing characteristics, as our airports cannot take larger planes. LeMay is urging two C-54 groups. With this airlift, we should be able to bring in 600 or 700 tons a day. While 2,000 tons a day is required in normal foods, 600 tons a day (utilizing dried foods to the maximum extent) will substantially increase the morale of the German people and will unquestionably seriously disturb the Soviet blockade. To accomplish this, it is urgent that we be given approximately 50 additional transport planes to arrive in Germany at the earliest practicable date, and each day's delay will of course decrease our ability to sustain our position in Berlin. Crews would be needed to permit maximum operation of these planes.

text: By 1 July, the system was getting under way. C-54s were starting to arrive in quantity, and Rhein-Main Air Base became exclusively a C-54 hub, while Wiesbaden retained a mix of C-54s and C-47s. Aircraft flew northeast through the American air corridor into Tempelhof Airport, then returned due west flying out on through the British air corridor. After reaching the British Zone, they turned south to return to their bases.[citation needed]

text: The British ran a similar system, flying southeast from several airports in the Hamburg area through their second corridor into RAF Gatow in the British Sector, and then also returning out on the center corridor, turning for home or landing at Hanover. However, unlike the Americans, the British also ran some round-trips, using their southeast corridor. On 6 July the Yorks and Dakotas were joined by Short Sunderland flying boats. Flying from Finkenwerder on the Elbe near Hamburg to the Havel river next to Gatow, their corrosion-resistant hulls suited them to the particular task of delivering baking powder and other salt into the city.[citation needed]

text: Accommodating the large number of flights to Berlin of dissimilar aircraft with widely varying flight characteristics required close co-ordination. Smith and his staff developed a complex timetable for flights called the "block system": three eight-hour shifts of a C-54 section to Berlin followed by a C-47 section. Aircraft were scheduled to take off every four minutes, flying 1,000 feet higher than the flight in front. This pattern began at 5,000 feet and was repeated five times. (This system of stacked inbound serials was later dubbed "the ladder.")[59][60][61]

text: During the first week the airlift averaged only ninety tons a day, but by the second week it reached 1,000 tons. This likely would have sufficed had the effort lasted only a few weeks, as originally believed. The Communist press in East Berlin ridiculed the project. It derisively referred to "the futile attempts of the Americans to save face and to maintain their untenable position in Berlin."[62]

text: Despite the excitement engendered by glamorous publicity extolling the work (and over-work) of the crews and the daily increase of tonnage levels, the airlift was not close to being operated to its capability because USAFE was a tactical organisation without any airlift expertise. Maintenance was barely adequate, crews were not being efficiently used, transports stood idle and disused, necessary record-keeping was scant, and ad hoc flight crews of publicity-seeking desk personnel were disrupting a business-like atmosphere.[63] This was recognised by the United States National Security Council at a meeting with Clay on 22 July 1948, when it became clear that a long-term airlift was necessary. Wedemeyer immediately recommended that the deputy commander for operations of the Military Air Transport Service (MATS), Maj. Gen. William H. Tunner, command the operation. When Wedemeyer had been the commander of US forces in China during World War II, Tunner as commander of the India-China Division of the Air Transport Command had reorganised the Hump airlift between India and China, doubling the tonnage and hours flown. USAF Chief of Staff Hoyt S. Vandenberg endorsed the recommendation.[59]

text: Black Friday[edit]

text: On 28 July 1948, Tunner arrived in Wiesbaden to take over the operation.[64] He revamped the entire airlift operation, reaching an agreement with LeMay to form the Combined Air Lift Task Force (CALTF) to control both the USAFE and RAF lift operations from a central location, which went into effect in mid-October 1948. MATS immediately deployed eight squadrons of C-54s—72 aircraft to Wiesbaden and Rhein-Main Air Base to reinforce the 54 already in operation, the first by 30 July and the remainder by mid-August, and two-thirds of all C-54 aircrew worldwide began transferring to Germany to allot three crews per aircraft.[65]

text: Two weeks after his arrival, on 13 August, Tunner decided to fly to Berlin to grant an award to Lt. Paul O. Lykins, an airlift pilot who had made the most flights into Berlin up to that time, a symbol of the entire effort to date.[66] Cloud cover over Berlin dropped to the height of the buildings, and heavy rain showers made radar visibility poor. A C-54 crashed and burned at the end of the runway, and a second one landing behind it burst its tires while trying to avoid it. A third transport ground looped after mistakenly landing on a runway under construction. In accordance with the standard procedures then in effect, all incoming transports including Tunner's, arriving every three minutes, were stacked above Berlin by air traffic control from 3,000 feet (910 m) to 12,000 feet (3,700 m) in bad weather, creating an extreme risk of mid-air collision. Newly unloaded planes were denied permission to take off to avoid that possibility and created a backup on the ground. While no one was killed, Tunner was embarrassed that the control tower at Tempelhof had lost control of the situation while the commander of the airlift was circling overhead. Tunner radioed for all stacked aircraft except his to be sent home immediately. This became known as "Black Friday," and Tunner personally noted it was from that date that the success of the airlift stemmed.[67][68]

text: As a result of Black Friday, Tunner instituted a number of new rules; instrument flight rules (IFR) would be in effect at all times, regardless of actual visibility, and each sortie would have only one chance to land in Berlin, returning to its air base if it missed its approach, where it was slotted back into the flow. Stacking was completely eliminated, and with straight-in approaches, the planners found that in the time it once took to unstack and land nine aircraft, 30 could be landed bringing in 300 tons.[69] Accident rates and delays dropped immediately. Another decision was made when it was realised that it took just as long to unload a 3.5-ton C-47 as a 10-ton C-54. One of the reasons for this was the sloping cargo floor of the "taildragger" C-47s, which made truck loading difficult. The tricycle geared C-54's cargo deck was level, so that a truck could back up to it and offload cargo quickly. Tunner decided, as he had done during the Hump operation, to replace all C-47s in the airlift with C-54s or larger aircraft, which went into full effect after 28 September 1948.[70]

text: Having noticed on his first inspection trip to Berlin on 31 July that there were long delays as the flight crews returned to their aircraft after getting refreshments from the terminal, Tunner banned aircrew from leaving their aircraft for any reason while in Berlin. Instead, he equipped jeeps as mobile snack bars, handing out refreshments to the crews at their aircraft while it was being unloaded. Gail Halvorsen later noted, "he put some beautiful German Fräuleins in that snack bar. They knew we couldn't date them, we had no time. So they were very friendly."[51] Operations officers handed pilots their clearance slips and other information while they snacked. With unloading begun as soon as engines were shut down on the ramp, turnaround before takeoff back to Rhein-Main or Wiesbaden was reduced to thirty minutes.[71]

text: To maximise utilization of a limited number of aircraft, Tunner altered the "ladder" to three minutes and 500 feet (150 m) of separation, stacked from 4,000 feet (1,200 m) to 6,000 feet (1,800 m).[60] Maintenance, particularly adherence to 25-hour, 200-hour, and 1000-hour inspections, became the highest priority and further maximised utilization.[72] Tunner also shortened block times to six hours to squeeze in another shift, making 1440 (the number of minutes in a day) landings in Berlin a daily goal.[nb 4] His purpose, illustrating his basic philosophy of the airlift business, was to create a "conveyor belt" approach to scheduling that could be sped up or slowed down as situations might dictate. The most effective measure taken by Tunner, and the most initially resisted until it demonstrated its efficiency, was creation of a single control point in the CALTF for controlling all air movements into Berlin, rather than each air force doing its own.

text: The Berliners themselves solved the other problem, the lack of manpower. Crews unloading and making airfield repairs at the Berlin airports were replaced almost entirely by local people, who were given additional rations in return. As the crews improved, the times for unloading continued to fall, with a record being set by the unloading of an entire 10-ton shipment of coal from a C-54 in ten minutes, later beaten when a twelve-man crew unloaded the same quantity in five minutes and 45 seconds.

text: By the end of August, after two months, the Airlift was succeeding; daily operations flew more than 1,500 flights a day and delivered more than 4,500 tons of cargo, enough to keep West Berlin supplied. From January 1949 forward, 225 C-54s (40% of USAF and USN Skymasters worldwide)[65] were devoted to the lift.[73][nb 5] Supplies improved to 5,000 tons a day.

text: "Operation Little Vittles"[edit]

text: Gail Halvorsen, one of the many Airlift pilots, decided to use his off time to fly into Berlin and make movies with his hand-held camera. He arrived at Tempelhof on 17 July on one of the C-54s and walked over to a crowd of children who had gathered at the end of the runway to watch the aircraft. He introduced himself and they started to ask him questions about the aircraft and their flights. As a goodwill gesture, he handed out his only two sticks of Wrigley's Doublemint Gum, and promised that, if they did not fight over them, the next time he returned he would drop off more. The children quickly divided up the pieces as best they could. Before he left them, a child asked him how they would know it was him flying over, and he replied, "I'll wiggle my wings."[48]

text: The next day, on his approach to Berlin, he rocked the aircraft and dropped some chocolate bars attached to a handkerchief parachute to the children waiting below. Every day after that the number of children increased and he made several more drops. Soon, there was a stack of mail in Base Ops addressed to "Uncle Wiggly Wings", "The Chocolate Uncle" and "The Chocolate Flier". His commanding officer was upset when the story appeared in the news, but when Tunner heard about it, he approved of the gesture and immediately expanded it into "Operation Little Vittles". Other pilots participated, and when news reached the US, children all over the country sent in their own candy to help out. Soon, major candy manufacturers joined in. In the end, over twenty three tons of candy were dropped on Berlin,[48] and the "operation" became a major propaganda success. The candy-dropping aircraft were christened "raisin bombers" by the German children.[74]

text: Soviet responses[edit]

text: The Soviets had an advantage in conventional military forces, but were preoccupied with rebuilding their war-torn economy and society. The U.S. had a stronger navy and air force, and had nuclear weapons. Neither side wanted a war; the Soviets did not disrupt the airlift.[75]

text: Initial reaction[edit]

text: As the tempo of the Airlift grew, it became apparent that the Western powers might be able to pull off the impossible: indefinitely supplying an entire city by air alone. In response, starting on 1 August, the Soviets offered free food to anyone who crossed into East Berlin and registered their ration cards there, but West Berliners overwhelmingly rejected Soviet offers of food.[76]

text: Throughout the airlift, Soviet and German communists subjected the hard-pressed West Berliners to sustained psychological warfare.[76] In radio broadcasts, they relentlessly proclaimed that all Berlin came under Soviet authority and predicted the imminent abandonment of the city by the Western occupying powers.[76] The Soviets also harassed members of the democratically elected citywide administration, which had to conduct its business in the city hall located in the Soviet sector.[76]

text: During the early months of the airlift, the Soviets used various methods to harass allied aircraft. These included buzzing by Soviet planes, obstructive parachute jumps within the corridors, and shining searchlights to dazzle pilots at night. Although the USAFE reported 733 separate harassing events, including flak, air-to-air fire, rocketing, bombing, and explosions, this is now considered to be exaggerated. None of these measures were effective.[77][78] Former RAF Dakota pilot Dick Arscott described one "buzzing" incident. "Yaks (Soviet plane) used to come and buzz you and go over the top of you at about twenty feet which can be off putting. One day I was buzzed about three times.. The following day it started again and he came across twice and I got a bit fed up with it. So when he came for the third time, I turned the aircraft into him and it was a case of chicken, luckily he was the one who chickened out." [79]

text: Attempted Communist putsch in the municipal government[edit]

text: In the autumn of 1948 it became impossible for the non-Communist majority in Greater Berlin's citywide parliament to attend sessions at city hall within the Soviet sector.[76] The parliament (Stadtverordnetenversammlung von Groß-Berlin) had been elected under the provisional constitution of Berlin two years earlier (20 October 1946). As SED-controlled policemen looked on passively, Communist-led mobs repeatedly invaded the Neues Stadthaus, the provisional city hall (located on Parochialstraße since all other central municipal buildings had been destroyed in the War), interrupted the parliament's sessions, and physically menaced its non-Communist members.[76] The Kremlin organised an attempted putsch for control of all of Berlin through a 6 September takeover of the city hall by SED members.[80]

text: Three days later RIAS Radio urged Berliners to protest against the actions of the communists. On 9 September 1948 a crowd of 500,000 people gathered at the Brandenburg Gate, next to the ruined Reichstag in the British sector. The Airlift was working so far, but many West Berliners feared that the Allies would eventually discontinue it. Then-SPD city councillor Ernst Reuter took the microphone and pleaded for his city, "You peoples of the world, you people of America, of England, of France, look on this city, and recognise that this city, this people, must not be abandoned – cannot be abandoned!".[51]

text: The crowd surged towards the eastern sector and someone ripped down the Red Flag from the Brandenburg Gate. Soviet military police responded, killing one.[51] The situation could have escalated further, but a British deputy provost intervened and pointedly pushed the Soviet police back with his swagger stick.[81] Never before had so many Berliners gathered. The resonance worldwide was enormous, notably in the United States, where a strong feeling of solidarity with Berliners reinforced a determination not to abandon them.[80]

text: Berlin's parliament decided to meet instead in the canteen of the Technical College of Berlin-Charlottenburg in the British sector, boycotted by the members of SED, which had gained 19.8% of the electoral votes in 1946. On 30 November 1948 the SED gathered its elected parliament members and 1,100 further activists and held an unconstitutional so-called "extraordinary city assembly" (außerordentliche Stadtverordnetenversammlung) in East Berlin's Metropol-Theater which declared the elected city government (Magistrat) and its democratic members (city councillors) to be deposed and replaced it with a new one led by Oberbürgermeister (lord mayor) Friedrich Ebert junior and consisting of communists only.[80] This arbitrary act had no legal effect in West Berlin, but the Soviet occupants prevented the elected city government for all of Berlin from further acting in the eastern sector.

text: December elections[edit]

text: The city parliament, boycotted by its SED members, then voted for its re-election on 5 December 1948, however, inhibited in the eastern sector and defamed by the SED as a Spalterwahl ("divisive election"). The SED did not nominate any candidates for this election and appealed to the electorate in the western sectors to boycott the election, while the democratic parties ran for seats. The turnout amounted to 86.3% of the western electorate with the SPD gaining 64.5% of the votes (= 76 seats), the CDU 19.4% (= 26 seats), and the Liberal-Demokratische Partei (LDP, merged in the FDP in 1949) 16.1% (= 17 seats).[76]

text: On 7 December the new, de facto West-Berlin-only city parliament elected a new city government in West Berlin headed by Lord Mayor Reuter, who had already once been elected lord mayor in early 1946 but prevented from taking office by a Soviet veto.[80] Thus two separate city governments officiated in the city divided into East and West versions of its former self. In the east, a communist system supervised by house, street, and block wardens was quickly implemented.

text: West Berlin's parliament accounted for the de facto political partition of Berlin and replaced the provisional constitution of Berlin by the Verfassung von Berlin (constitution of Berlin), meant for all Berlin, with effect of 1 October 1950 and de facto restricted to the western sectors only, also renaming city parliament (from Stadtverordnetenversammlung von Groß-Berlin to Abgeordnetenhaus von Berlin), city government (from Magistrat von Groß-Berlin to Senate of Berlin), and head of government (from Oberbürgermeister to Governing Mayor of Berlin).[82]

text: Winter 1948 to spring 1949[edit]

text: This section needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (June 2011) (Learn how and when to remove this template message)

text: Preparing for winter[edit]

text: Although the early estimates were that about 4,000 to 5,000 tons per day would be needed to supply the city, this was made in the context of summer weather, when the Airlift was only expected to last a few weeks. As the operation dragged on into autumn, the situation changed considerably. The food requirements would remain the same (around 1,500 tons), but the need for additional coal to heat the city dramatically increased the total amount of cargo to be transported by an additional 6,000 tons a day.

text: To maintain the Airlift under these conditions, the current system would have to be greatly expanded. Aircraft were available, and the British started adding their larger Handley Page Hastings in November, but maintaining the fleet proved to be a serious problem. Tunner looked to the Germans once again, hiring (plentiful) ex-Luftwaffe ground crews.

text: Another problem was the lack of runways in Berlin to land on: two at Tempelhof and one at Gatow — neither of which was designed to support the loads the C-54s were putting on them. All of the existing runways required hundreds of labourers, who ran onto them between landings and dumped sand into the runway's Marston Mat (pierced steel planking) to soften the surface and help the planking survive. Since this system could not endure through the winter, between July and September 1948 a 6,000 ft.-long asphalt runway was constructed at Tempelhof.

text: Far from ideal, with the approach being over Berlin's apartment blocks, the runway nevertheless was a major upgrade to the airport's capabilities. With it in place, the auxiliary runway was upgraded from Marston Matting to asphalt between September and October 1948. A similar upgrade program was carried out by the British at Gatow during the same period, also adding a second runway, using concrete.

text: The French Air Force, meanwhile, had become involved in the First Indochina War, so it could only bring up some old Junkers Ju 52s to support its own troops and they were too small and slow to be of much help. However, France agreed to build a complete, new and larger airport in its sector on the shores of Lake Tegel. French military engineers, managing German construction crews, were able to complete the construction in under 90 days. The airport was mostly built by hand, by thousands of mostly female labourers who worked day and night.[83]

text: Heavy equipment was needed to level the ground, equipment that was too large and heavy to fly in on any existing cargo aircraft. The solution was to dismantle large machines and then re-assemble them. Using the five largest American C-82 Packet transports, it was possible to fly the machinery into West Berlin. This not only helped to build the airfield, but also demonstrated that the Soviet blockade could not keep anything out of Berlin. The Tegel airfield was subsequently developed into Berlin-Tegel Airport.

text: To improve air traffic control, which would be critical as the number of flights grew, the newly developed Ground Controlled Approach radar system (GCA) was flown to Europe for installation at Tempelhof, with a second set installed at Fassberg in the British Zone in West Germany. With the installation of GCA, all-weather airlift operations were assured.

text: None of these efforts could fix the weather: which became the biggest problem. November and December 1948 proved to be the worst months of the airlift operation. One of the longest-lasting fogs ever experienced in Berlin blanketed the entire European continent for weeks. All too often, aircraft would make the entire flight and then be unable to land in Berlin. On 20 November, 42 aircraft departed for Berlin, but only one landed there. At one point, the city had only a week's supply of coal left. However, the weather eventually improved, and more than 171,000 tons were delivered in January 1949, 152,000 tons in February, and 196,223 tons in March.[62]

text: Easter parade[edit]

text: By April 1949, airlift operations were running smoothly and Tunner wanted to shake up his command to discourage complacency. He believed in the spirit of competition between units and, coupled with the idea of a big event, felt that this would encourage them to greater efforts. He decided that, on Easter Sunday, the airlift would break all records. To do this, maximum efficiency was needed and so, to simplify cargo-handling, only coal would be airlifted. Coal stockpiles were built up for the effort and maintenance schedules were altered so that the maximum number of aircraft were available.[84]

text: From noon on 15 April to noon on 16 April 1949, crews worked around the clock. When it was over, 12,941 tons of coal had been delivered in 1,383 flights, without a single accident.[84] A welcome side effect of the effort was that operations in general were boosted, and tonnage increased from 6,729 tons to 8,893 tons per day thereafter. In total, the airlift delivered 234,476 tons in April.[62]

text: On 21 April, the tonnage of supplies flown into the city exceeded that previously brought by rail.[citation needed]

text: End of the blockade[edit]

text: On 15 April 1949, the Russian news agency TASS reported a willingness by the Soviets to lift the blockade. The next day, the US State Department stated that the "way appears clear" for the blockade to end. Soon afterwards, the four powers began serious negotiations, and a settlement was reached, on Western terms. On 4 May 1949, the Allies announced an agreement to end the blockade in eight days' time.

text: The Soviet blockade of Berlin was lifted at one minute after midnight on 12 May 1949.[85] A British convoy immediately drove through to Berlin, and the first train from West Germany reached Berlin at 5:32 A.M. Later that day, an enormous crowd celebrated the end of the blockade. General Clay, whose retirement had been announced by US President Truman on 3 May, was saluted by 11,000 US soldiers and dozens of aircraft. Once home, Clay received a ticker-tape parade in New York City, was invited to address the US Congress, and was honoured with a medal from President Truman.

text: Nevertheless, flights continued for some time, to build up a comfortable surplus, though night flying and then weekend flights could be eliminated once the surplus was large enough. By 24 July 1949, three months' worth of supplies had been amassed, ensuring that there was ample time to restart the Airlift if needed.

text: The Berlin Airlift officially ended on 30 September 1949, after fifteen months. In total, the USA delivered 1,783,573 tons and the RAF 541,937 tons,[nb 6] totalling 2,326,406 tons, nearly two-thirds of which was coal, on 278,228 flights to Berlin.[86] The Royal Australian Air Force delivered 7,968 tons of freight and 6,964 passengers during 2,062 sorties. The C-47s and C-54s together flew over 92 million miles in the process, almost the distance from Earth to the Sun.[86] At the height of the Airlift, one plane reached West Berlin every thirty seconds.[85]

text: Pilots came from the United States, United Kingdom, Australia, Canada, New Zealand, and South Africa.[87][88]

text: A total of 101 fatalities were recorded as a result of the operation, including 40 Britons and 31 Americans,[85] mostly due to non-flying accidents.[89] Seventeen American and eight British aircraft crashed during the operation.

text: The cost of the Airlift was shared between the USA, UK, and Germany. Estimated costs range from approximately US$224 million[90] to over US$500 million (equivalent to approximately $2.25 billion to $5.03 billion now).[91][87][92]

text: Subsequent events[edit]

text: Operational control of the three Allied air corridors was assigned to BARTCC (Berlin Air Route Traffic Control Center) air traffic control located at Tempelhof. Diplomatic approval was granted by a four-power organisation called the Berlin Air Safety Center, also located in the American sector.

text: Tegel was developed into West Berlin's principal airport. In 2007, it was joined by a re-developed Berlin-Schönefeld International Airport in Brandenburg. As a result of the development of these two airports, Tempelhof was closed in October 2008,[93] while Gatow is now home of the Museum of the German Luftwaffe and a housing development. During the 1970s and 1980s Schönefeld had its own crossing points through the Berlin Wall and communist fortifications for western citizens.

text: The Soviets' contravention by the blockade of the agreement reached by the London 6-Power Conference, and the Czechoslovak coup d'état of 1948, convinced Western leaders that they had to take swift and decisive measures to strengthen the portions of Germany not occupied by the Soviets.[85] The Blockade also helped to overcome any remaining differences between the French, British and Americans regarding West Germany, leading to a merger of the three countries' occupation zones into "trizonia".[94]

text: These countries also agreed to replace their military administrations in those zones with High Commissioners operating within the terms of a three-power occupation statute.[94] The Blockade also helped to unify German politicians in these zones in support of the creation of a West German state; some of them had hitherto been fearful of Soviet opposition.[94] The blockade also increased the perception among many Europeans that the Soviets posed a danger, helping to prompt the entry into NATO of Portugal, Iceland, Italy, Denmark, and Norway.[95]

text: Animosities between Germans and the western Allies – Britain, France and the United States – were greatly reduced by the airlift, with the former enemies recognizing common interests, shared values and mutual respect.[96] The Soviets refused to return to the Allied Control Council in Berlin, rendering the four-power occupation authority set up at the Potsdam conference useless.[85] It has been argued that the events of the Berlin Blockade are proof that the Allies conducted their affairs within a rational framework, since they were keen to avoid war.[97]

text: Aircraft used in the Berlin Airlift[edit]

text: In the early days, the Americans used their C-47 Skytrain or its civilian counterpart Douglas DC-3. These machines could carry a payload of up to 3.5 tons, but were replaced by C-54 Skymasters and Douglas DC-4s, which could carry up to 10 tons and were faster. These made up a total of 330 aircraft, which made them the most used types. Other American aircraft such as the 5 C-82 Packets, and the one YC-97A Stratofreighter 45-59595, with a payload of 20 tons—a gigantic load for that time—were only sparsely used.

text: The British used a considerable variety of aircraft types. Many aircraft were either former bombers or civil versions of bombers. In the absence of enough transports, the British chartered many civilian aircraft. British European Airways (BEA) coordinated all British civil aircraft operations. Apart from BEA itself, the participating airlines included British Overseas Airways Corporation (BOAC) and most British independent[nb 7] airlines of that era – e.g. Eagle Aviation,[98] Silver City Airways, British South American Airways (BSAA), the Lancashire Aircraft Corporation, Airwork, Air Flight, Aquila Airways, Flight Refuelling Ltd (which used their Lancaster tankers to deliver aviation fuel), Skyways, Scottish Airlines and Ciro's Aviation.

text: Altogether, BEA was responsible to the RAF for the direction and operation of 25 British airlines taking part in "Operation Plainfare".[99] The British also used flying boats, particularly for transporting corrosive salt. These included civilian aircraft operated by Aquila Airways.[100] These took off and landed on water and were designed to be corrosion-resistant. In winter, when ice covered the Berlin rivers and made the use of flying boats difficult, the British used other aircraft in their place.

text:
Avro Lancaster
Avro Lincoln
Avro York
Avro Tudor
Avro Lancastrian
Boeing C-97 Stratofreighter
Bristol Type 170 Freighter
Consolidated B-24 Liberator
Consolidated PBY Catalina
Douglas C-54 Skymaster and Douglas DC-4
Douglas C-74 Globemaster
Douglas C-47 Skytrain and Douglas DC-3 (UK: Dakota)
Fairchild C-82 Packet
Handley Page Hastings
Handley Page Halifax Halton
Junkers Ju 52/3m (operated briefly by France)
Lockheed C-121A Constellation
Short Sunderland
Vickers VC.1 Viking

tag: ul

text: Altogether, a total of 692 aircraft were engaged in the Berlin Airlift, more than 100 of which belonged to civilian operators.[101]


document_title: History of programming languages

question_text: where was the first high-level language operating system created

root

text: History of programming languages

text: Introduction[edit]

text: Even though a huge number of computer languages exist, the earliest computers were programmed in binary so the set of instructions was just a series of 0 and 1. Computer languages are a fairly new field, since the first high-level languages were written in the 1950s, around the time computers were invented. Before computer programming languages were made, paper tapes and punch cards which held complicated weaving patterns for the loom Tabulating Machine Company Looms by Jacquard in 1710. A century later, Charles Babbage started building a computing and the analytical Machine. In the 20th century, Herman Hollerith founded the Tabulating Machine. His machine tabulators were used to speed up the counting and sorting of punch cards. In the early 1940s J. Presper Eckert and John W. Mauchly started building the ENIAC (Electronic Numerical Integrator and Calculator), which was completed by 1946.

tag: p

text: The very first high-level programming language was FORTRAN, which stands for FORmula TRANslation. It was developed in 1956 (first manual appeared in 1956, but first developed in 1954) by John Backus, a worker at IBM. FORTRAN's goal was to ease the pain of writing in assembly language. When FORTRAN was first introduced, it was looked on suspiciously since almost all the programmers then only worked with the machine code and assembly languages. The programmers at that time had an initial belief that programs compiled from high-level language would be less efficient than those written at low-level. In order to persuade potential users of the benefits of working with a high-level language, Backus designed an excellent compiler for FORTRAN so the programs were just as efficient as those written in low-level languages. This was the best compiler for many years.

text: FORTRAN soon became popular because it provided a realistic and desirable alternative to low-level language programming for mathematical and scientific applications. This programming language was also the first to be widely used. However, one of the limitations of FORTRAN was that it was specifically oriented toward the IBM 704 machine. This is a major set-back since the language syntax contains many idiosyncrasies from the IBM 704 machine. From a pure programming language design standpoint this is a "cardinal sin" but historically, it is understandable. FORTRAN is known for its efficiency. Over the years, FORTRAN had been upgraded and developed into FORTRAN -II, FORTRAN -IV, FORTRAN -66, and FORTRAN -77. Early versions of FORTRAN largely restricted users. On the other hand, the later versions allowed more flexibility, but since it has adapted, it is not as easy to use as it should be. The development of the fast string processing makes FORTRAN more of a general-purpose language than it used to be, but it is still described as a mathematical or scientific language.

text: Early history[edit]

text: During a nine-month period in 1842–1843, Ada Lovelace translated the memoir of Italian mathematician Luigi Menabrea about Charles Babbage's newest proposed machine, the analytical engine. With the article she appended a set of notes which specified in complete detail a method for calculating Bernoulli numbers with the engine, recognized by some historians as the world's first computer program.[1]

text: Herman Hollerith realized that he could encode information on punch cards when he observed that train conductors encode the appearance of the ticket holders on the train tickets using the position of punched holes on the tickets[2]. Hollerith then encoded the 1890 American census data on punch cards.

text: The first computer codes were specialized for their applications. In the first decades of the 20th century, numerical calculations were based on decimal numbers. Eventually it was realized that logic could be represented with numbers, not only with words. For example, Alonzo Church was able to express the lambda calculus in a formulatic way. The Turing machine was an abstraction of the operation of a tape-marking machine, for example, in use at the telephone companies. Turing machines set the basis for storage of programs as data in the von Neumann architecture of computers by representing a machine through a finite number. However, unlike the lambda calculus, Turing's code does not serve well as a basis for higher-level languages—its principal use is in rigorous analyses of algorithmic complexity.

text: Like many "firsts" in history, the first modern programming language is hard to identify. From the start, the restrictions of the hardware defined the language. Punch cards allowed 80 columns, but some of the columns had to be used for a sorting number on each card. FORTRAN included some keywords which were the same as English words, such as "IF", "GOTO" (go to) and "CONTINUE". The use of a magnetic drum for memory meant that computer programs also had to be interleaved with the rotations of the drum. Thus the programs were more hardware-dependent.

text: To some people, what was the first modern programming language depends on how much power and human-readability is required before the status of "programming language" is granted. Jacquard Looms and Charles Babbage's Difference Engine both had simple, extremely limited languages for describing the actions that these machines should perform. One can even regard the punch holes on a player piano scroll as a limited domain-specific language, albeit not designed for human consumption.

text: First programming languages[edit]

text: In the 1940s, the first recognizably modern electrically powered computers were created. The limited speed and memory capacity forced programmers to write hand tuned assembly language programs. It was eventually realized that programming in assembly language required a great deal of intellectual effort.

text: The first programming languages designed to communicate instructions to a computer were written in the 1950s. An early high-level programming language to be designed for a computer was Plankalkül, developed by the Germans for Z1 by Konrad Zuse between 1943 and 1945. However, it was not implemented until 1998 and 2000.[3]

text: John Mauchly's Short Code, proposed in 1949, was one of the first high-level languages ever developed for an electronic computer.[4] Unlike machine code, Short Code statements represented mathematical expressions in understandable form. However, the program had to be translated into machine code every time it ran, making the process much slower than running the equivalent machine code.

text: At the University of Manchester, Alick Glennie developed Autocode in the early 1950s. A programming language, it used a compiler to automatically convert the language into machine code. The first code and compiler was developed in 1952 for the Mark 1 computer at the University of Manchester and is considered to be the first compiled high-level programming language.[5][6]

text: The second autocode was developed for the Mark 1 by R. A. Brooker in 1954 and was called the "Mark 1 Autocode". Brooker also developed an autocode for the Ferranti Mercury in the 1950s in conjunction with the University of Manchester. The version for the EDSAC 2 was devised by D. F. Hartley of University of Cambridge Mathematical Laboratory in 1961. Known as EDSAC 2 Autocode, it was a straight development from Mercury Autocode adapted for local circumstances, and was noted for its object code optimisation and source-language diagnostics which were advanced for the time. A contemporary but separate thread of development, Atlas Autocode was developed for the University of Manchester Atlas 1 machine.

text: In 1954, language FORTRAN was invented at IBM by John Backus; it was the first widely used high level general purpose programming language to have a functional implementation, as opposed to just a design on paper.[7][8] It is still a popular language for high-performance computing[9] and is used for programs that benchmark and rank the world's fastest supercomputers.[10]

text: Another early programming language was devised by Grace Hopper in the US, called FLOW-MATIC. It was developed for the UNIVAC I at Remington Rand during the period from 1955 until 1959. Hopper found that business data processing customers were uncomfortable with mathematical notation, and in early 1955, she and her team wrote a specification for an English programming language and implemented a prototype.[11] The FLOW-MATIC compiler became publicly available in early 1958 and was substantially complete in 1959.[12] Flow-Matic was a major influence in the design of COBOL, since only it and its direct descendent AIMACO were in actual use at the time.[13]

text: Other languages still in use today include LISP (1958), invented by John McCarthy and COBOL (1959), created by the Short Range Committee. Another milestone in the late 1950s was the publication, by a committee of American and European computer scientists, of "a new language for algorithms"; the ALGOL 60 Report (the "ALGOrithmic Language"). This report consolidated many ideas circulating at the time and featured three key language innovations:

text:
nested block structure: code sequences and associated declarations could be grouped into blocks without having to be turned into separate, explicitly named procedures;
lexical scoping: a block could have its own private variables, procedures and functions, invisible to code outside that block, that is, information hiding.

text: Another innovation, related to this, was in how the language was described:

text: a mathematically exact notation, Backus–Naur form (BNF), was used to describe the language's syntax. Nearly all subsequent programming languages have used a variant of BNF to describe the context-free portion of their syntax.

text: Algol 60 was particularly influential in the design of later languages, some of which soon became more popular. The Burroughs large systems were designed to be programmed in an extended subset of Algol.

text: Algol's key ideas were continued, producing ALGOL 68:

text:
syntax and semantics became even more orthogonal, with anonymous routines, a recursive typing system with higher-order functions, etc.;
not only the context-free part, but the full language syntax and semantics were defined formally, in terms of Van Wijngaarden grammar, a formalism designed specifically for this purpose.

text: Algol 68's many little-used language features (for example, concurrent and parallel blocks) and its complex system of syntactic shortcuts and automatic type coercions made it unpopular with implementers and gained it a reputation of being difficult. Niklaus Wirth actually walked out of the design committee to create the simpler Pascal language.

text: Some notable languages that were developed in this period include:

text:
1951 – Regional Assembly Language
1952 – Autocode
1954 – IPL (forerunner to LISP)
1955 – FLOW-MATIC (led to COBOL)
1957 – FORTRAN (First compiler)
1957 – COMTRAN (precursor to COBOL)
1958 – LISP
1958 – ALGOL 58
1959 – FACT (forerunner to COBOL)
1959 – COBOL

1959 – RPG
1962 – APL
1962 – Simula
1962 – SNOBOL
1963 – CPL (forerunner to C)
1964 – Speakeasy (computational environment)
1964 – BASIC
1964 – PL/I
1966 – JOSS
1967 – BCPL (forerunner to C)

tag: table

text: Establishing fundamental paradigms[edit]

text: The period from the late 1960s to the late 1970s brought a major flowering of programming languages. Most of the major language paradigms now in use were invented in this period:

text:
Speakeasy (computational environment), developed in 1964 at Argonne National Laboratory (ANL) by Stanley Cohen, is an OOPS (object-oriented programming, much like the later MATLAB, IDL (programming language) and Mathematica) numerical package. Speakeasy has a clear Fortran foundation syntax. It first addressed efficient physics computation internally at ANL, was modified for research use (as "Modeleasy") for the Federal Reserve Board in the early 1970s and then was made available commercially; Speakeasy and Modeleasy are still in use currently.
Simula, invented in the late 1960s by Nygaard and Dahl as a superset of Algol 60, was the first language designed to support object-oriented programming.
C, an early systems programming language, was developed by Dennis Ritchie and Ken Thompson at Bell Labs between 1969 and 1973.
Smalltalk (mid-1970s) provided a complete ground-up design of an object-oriented language.
Prolog, designed in 1972 by Colmerauer, Roussel, and Kowalski, was the first logic programming language.
ML built a polymorphic type system (invented by Robin Milner in 1973) on top of Lisp,[14] pioneering statically typed functional programming languages.

text: Each of these languages spawned an entire family of descendants, and most modern languages count at least one of them in their ancestry.

text: The 1960s and 1970s also saw considerable debate over the merits of "structured programming", which essentially meant programming without the use of "goto". A significant fraction of programmers believed that, even in languages that provide "goto", it is bad programming style to use it except in rare circumstances. This debate was closely related to language design: some languages did not include a "goto" at all, which forced structured programming on the programmer.

text: To provide even faster compile times, some languages were structured for "one-pass compilers" which expect subordinate routines to be defined first, as with Pascal, where the main routine, or driver function, is the final section of the program listing.

text:
1968 – Logo
1969 – B (forerunner to C)
1970 – Pascal
1970 – Forth
1972 – C

1972 – Smalltalk
1972 – Prolog
1973 – ML
1975 – Scheme
1978 – SQL (a query language, later extended)

text: 1980s: consolidation, modules, performance[edit]

text: The 1980s were years of relative consolidation in imperative languages. Rather than inventing new paradigms, all of these movements elaborated upon the ideas invented in the previous decade. C++ combined object-oriented and systems programming. The United States government standardized Ada, a systems programming language intended for use by defense contractors. In Japan and elsewhere, vast sums were spent investigating so-called fifth-generation programming languages that incorporated logic programming constructs. The functional languages community moved to standardize ML and Lisp. Research in Miranda, a functional language with lazy evaluation, began to take hold in this decade.

text: One important new trend in language design was an increased focus on programming for large-scale systems through the use of modules, or large-scale organizational units of code. Modula, Ada, and ML all developed notable module systems in the 1980s. Module systems were often wedded to generic programming constructs---generics being, in essence, parametrized modules[citation needed] (see also polymorphism in object-oriented programming).

text: Although major new paradigms for imperative programming languages did not appear, many researchers expanded on the ideas of prior languages and adapted them to new contexts. For example, the languages of the Argus and Emerald systems adapted object-oriented programming to distributed systems.

text: The 1980s also brought advances in programming language implementation. The RISC movement in computer architecture postulated that hardware should be designed for compilers rather than for human assembly programmers. Aided by processor speed improvements that enabled increasingly aggressive compilation techniques, the RISC movement sparked greater interest in compilation technology for high-level languages.

text: Language technology continued along these lines well into the 1990s.

text:
1980 – C++ (as C with classes, renamed in 1983)
1983 – Ada
1984 – Common Lisp
1984 – MATLAB
1984 - FoxPro (as FoxBASE, later developing into Visual FoxPro
1985 – Eiffel
1986 – Objective-C

1986 – LabVIEW (Visual Programming Language)
1986 – Erlang
1987 – Perl
1988 – Tcl
1988 – Wolfram Language (as part of Mathematica, only got a separate name in June 2013)
1989 – FL (Backus)

text: 1990s: the Internet age[edit]

text: The rapid growth of the Internet in the mid-1990s was the next major historic event in programming languages. By opening up a radically new platform for computer systems, the Internet created an opportunity for new languages to be adopted. In particular, the JavaScript programming language rose to popularity because of its early integration with the Netscape Navigator web browser. Various other scripting languages achieved widespread use in developing customized applications for web servers such as PHP. The 1990s saw no fundamental novelty in imperative languages, but much recombination and maturation of old ideas. This era began the spread of functional languages. A big driving philosophy was programmer productivity. Many "rapid application development" (RAD) languages emerged, which usually came with an IDE, garbage collection, and were descendants of older languages. All such languages were object-oriented. These included Object Pascal, Visual Basic, and Java. Java in particular received much attention.

text: More radical and innovative than the RAD languages were the new scripting languages. These did not directly descend from other languages and featured new syntaxes and more liberal incorporation of features. Many consider these scripting languages to be more productive than even the RAD languages, but often because of choices that make small programs simpler but large programs more difficult to write and maintain.[citation needed] Nevertheless, scripting languages came to be the most prominent ones used in connection with the Web.

text:
1990 – Haskell
1991 – Python
1991 – Visual Basic
1993 – Ruby
1993 – Lua
1993 – R
1994 – CLOS (part of ANSI Common Lisp)

1995 – Ada 95
1995 – Java
1995 – Delphi (Object Pascal)
1995 – JavaScript
1995 – PHP
1997 – Rebol
1999 – D

text: Current trends[edit]

text: This section needs to be updated. Please update this article to reflect recent events or newly available information. (May 2015)

text: This section possibly contains original research. Please improve it by verifying the claims made and adding inline citations. Statements consisting only of original research should be removed. (February 2015) (Learn how and when to remove this template message)

text: Programming language evolution continues, in both industry and research. Some of the recent trends have included:

text:
Increasing support for functional programming in mainstream languages used commercially, including pure functional programming for making code easier to reason about and easier to parallelise (at both micro- and macro- levels)
Constructs to support concurrent and distributed programming.
Mechanisms for adding security and reliability verification to the language: extended static checking, dependent typing, information flow control, static thread safety.
Alternative mechanisms for composability and modularity: mixins, traits, delegates, aspects.
Component-oriented software development.
Metaprogramming, reflection or access to the abstract syntax tree

AOP or Aspect Oriented Programming allowing developers to insert code in another module or class at "join points"
Domain specific languages and code generation

XML for graphical interface (XUL, XAML)

Increased interest in distribution and mobility.
Integration with databases, including XML and relational databases.
Open source as a developmental philosophy for languages, including the GNU Compiler Collection and languages such as Python, Ruby, and Scala.
Massively parallel languages for coding 2000 processor GPU graphics processing units and supercomputer arrays including OpenCL
Early research into (as-yet-unimplementable) quantum computing programming languages

text: Some notable languages developed during this period include:

text:
2000 – ActionScript
2001 – C#
2003 – Apache Groovy
2003 – Scala
2005 – F#
2006 – Windows PowerShell
2007 – Clojure

2009 – Go
2010 – Rust
2011 – Dart
2011 – Kotlin
2012 – Julia
2014 – Swift

text: Prominent people[edit]

text: Some key people who helped develop programming languages:

text:
Alan Cooper, developer of Visual Basic.
Alan Kay, pioneering work on object-oriented programming, and originator of Smalltalk.
Anders Hejlsberg, developer of Turbo Pascal, Delphi, C#, and TypeScript.
Bertrand Meyer, inventor of Eiffel.
Bjarne Stroustrup, developer of C++.
Brian Kernighan, co-author of the first book on the C programming language with Dennis Ritchie, coauthor of the AWK and AMPL programming languages.
Dennis Ritchie, inventor of C. Unix Operating System, Plan 9 Operating System.
Edsger W. Dijkstra, developed the framework for structured programming.
Grace Hopper, inventor of the first compiler and developer of Flow-Matic, influencing COBOL. Popularized machine-independent programming languages and the term "debugging".
Guido van Rossum, creator of Python.
James Gosling, lead developer of Java and it's precursor, Oak.
Jean Ichbiah, chief designer of Ada, Ada 83
Jean-Yves Girard, co-inventor of the polymorphic lambda calculus (System F).
Jeff Bezanson, got a PhD for the Julia language, one of the designers, and one of the core developers (and only developer of FemtoLisp).
Joe Armstrong, creator of Erlang.
John Backus, inventor of Fortran and cooperated in the design of ALGOL 58 and ALGOL 60.
John C. Reynolds, co-inventor of the polymorphic lambda calculus (System F).
John McCarthy, inventor of LISP.
John von Neumann, originator of the operating system concept.
Ken Thompson, inventor of B, Go Programming Language, Inferno Programming Language, and Unix Operating System co-author.
Kenneth E. Iverson, developer of APL, and co-developer of J along with Roger Hui.
Konrad Zuse, designed the first high-level programming language, Plankalkül (which influenced ALGOL 58[15]).
Kristen Nygaard, pioneered object-oriented programming, co-invented Simula.
Larry Wall, creator of the Perl programming language (see Perl and Perl 6).
Martin Odersky, creator of Scala, and previously a contributor to the design of Java.
Nathaniel Rochester, inventor of first assembler (IBM 701).
Niklaus Wirth, inventor of Pascal, Modula and Oberon.
Ole-Johan Dahl, pioneered object-oriented programming, co-invented Simula.
Rich Hickey, creator of Clojure.
Robin Milner, inventor of ML, and sharing credit for Hindley–Milner polymorphic type inference.
Stephen Wolfram, creator of Mathematica.
Yukihiro Matsumoto, creator of Ruby.


document_title: Placenta

question_text: placenta develops from the outer cells of the

text: Placenta

text: Structure[edit]

text: Placental mammals, such as humans, have a chorioallantoic placenta that forms from the chorion and allantois. In humans, the placenta averages 22 cm (9 inch) in length and 2–2.5 cm (0.8–1 inch) in thickness, with the center being the thickest, and the edges being the thinnest. It typically weighs approximately 500 grams (just over 1 lb). It has a dark reddish-blue or crimson color. It connects to the fetus by an umbilical cord of approximately 55–60 cm (22–24 inch) in length, which contains two umbilical arteries and one umbilical vein.[5] The umbilical cord inserts into the chorionic plate (has an eccentric attachment). Vessels branch out over the surface of the placenta and further divide to form a network covered by a thin layer of cells. This results in the formation of villous tree structures. On the maternal side, these villous tree structures are grouped into lobules called cotyledons. In humans, the placenta usually has a disc shape, but size varies vastly between different mammalian species.[6]

text: Physiology[edit]

text: Development[edit]

text: The placenta begins to develop upon implantation of the blastocyst into the maternal endometrium. The outer layer of the blastocyst becomes the trophoblast, which forms the outer layer of the placenta. This outer layer is divided into two further layers: the underlying cytotrophoblast layer and the overlying syncytiotrophoblast layer. The syncytiotrophoblast is a multinucleated continuous cell layer that covers the surface of the placenta. It forms as a result of differentiation and fusion of the underlying cytotrophoblast cells, a process that continues throughout placental development. The syncytiotrophoblast (otherwise known as syncytium), thereby contributes to the barrier function of the placenta.

text: The placenta grows throughout pregnancy. Development of the maternal blood supply to the placenta is complete by the end of the first trimester of pregnancy (approximately 12–13 weeks).

text: Placental circulation[edit]

text: Maternal placental circulation[edit]

text: In preparation for implantation of the blastocyst, the uterine endometrium undergoes "decidualisation". Spiral arteries in decidua are remodeled so that they become less convoluted and their diameter is increased. The increased diameter and straighter flow path both act to increase maternal blood flow to the placenta. There is relatively high pressure as the maternal blood fills intervillous space through these spiral arteries bathes the fetal villi in blood, allowing an exchange of gases to take place. In humans and other hemochorial placentals, the maternal blood comes into direct contact with the fetal chorion, though no fluid is exchanged. As the pressure decreases between pulses, the deoxygenated blood flows back through the endometrial veins.

text: Maternal blood flow is approximately 600–700 ml/min at term.

text: Fetoplacental circulation[edit]

text: Deoxygenated fetal blood passes through umbilical arteries to the placenta. At the junction of umbilical cord and placenta, the umbilical arteries branch radially to form chorionic arteries. Chorionic arteries, in turn, branch into cotyledon arteries. In the villi, these vessels eventually branch to form an extensive arterio-capillary-venous system, bringing the fetal blood extremely close to the maternal blood; but no intermingling of fetal and maternal blood occurs ("placental barrier").[7]

text: Endothelin and prostanoids cause vasoconstriction in placental arteries, while nitric oxide causes vasodilation.[8] On the other hand, there is no neural vascular regulation, and catecholamines have only little effect.[8]

text: The fetoplacental circulation is vulnerable to persistent hypoxia or intermittent hypoxia and reoxygenation, which can lead to generation of excessive free radicals. This may contribute to pre-eclampsia and other pregnancy complications.[9] It is proposed that melatonin plays a role as an antioxidant in the placenta.[9]

text: Birth[edit]

text: Placental expulsion begins as a physiological separation from the wall of the uterus. The period from just after the child is born until just after the placenta is expelled is called the "third stage of labor". The placenta is usually expelled within 15–30 minutes of birth.

text: Placental expulsion can be managed actively, for example by giving oxytocin via intramuscular injection followed by cord traction to assist in delivering the placenta. Alternatively, it can be managed expectantly, allowing the placenta to be expelled without medical assistance. A Cochrane study suggests that blood loss and the risk of postpartum bleeding will be reduced in women offered active management of the third stage of labour.[10]

text: The habit is to cut the cord immediately after birth, but allegedly there is no medical reason to do this; on the contrary, it is theorized that not cutting the cord helps the baby in its adaptation to extrauterine life, especially in preterm infants.[11]

text: Microbiome[edit]

text: The placenta was once thought to be sterile. Instead, a resident, non-pathogenic, and diverse population of microorganisms are present in healthy tissue. The uterus and its tissues are not sterile.[12][13][14][15]

text: Functions[edit]

text: Nutrition[edit]

text: The placenta intermediates the transfer of nutrients between mother and fetus. The perfusion of the intervillous spaces of the placenta with maternal blood allows the transfer of nutrients and oxygen from the mother to the fetus and the transfer of waste products and carbon dioxide back from the fetus to the maternal blood. Nutrient transfer to the fetus can occur via both active and passive transport.[16] Placental nutrient metabolism was found to play a key role in limiting the transfer of some nutrients.[17] Adverse pregnancy situations, such as those involving maternal diabetes or obesity, can increase or decrease levels of nutrient transporters in the placenta potentially resulting in overgrowth or restricted growth of the fetus.[18]

text: Excretion[edit]

text: Waste products excreted from the fetus such as urea, uric acid, and creatinine are transferred to the maternal blood by diffusion across the placenta.

text: Immunity[edit]

text: IgG antibodies can pass through the human placenta, thereby providing protection to the fetus in utero.[19] This transfer of antibodies begins as early as the 20th week of gestational age, and certainly by the 24th week.[20] This passive immunity lingers for several months after birth, thus providing the newborn with a carbon copy of the mother's long-term humoral immunity to see the infant through the crucial first months of extrauterine life. IgM, however, cannot cross the placenta, which is why some infections acquired during pregnancy can be hazardous for the fetus.

text: Furthermore, the placenta functions as a selective maternal-fetal barrier against transmission of microbes. However, insufficiency in this function may still cause mother-to-child transmission of infectious diseases.

text: Endocrine function[edit]

text:
The first hormone released by the placenta is called the human chorionic gonadotropin hormone. This is responsible for stopping the process at the end of menses when the Corpus luteum ceases activity and atrophies. If hCG did not interrupt this process, it would lead to spontaneous abortion of the fetus. The corpus luteum also produces and releases progesterone and estrogen, and hCG stimulates it to increase the amount that it releases. hCG is the indicator of pregnancy that pregnancy tests look for. These tests will work when menses has not occurred or after implantation has happened on days seven to ten. hCG may also have an anti-antibody effect, protecting it from being rejected by the mother’s body. hCG also assists the male fetus by stimulating the testes to produce testosterone, which is the hormone needed to allow the sex organs of the male to grow.
Progesterone helps the embryo implant by assisting passage through the fallopian tubes. It also affects the fallopian tubes and the uterus by stimulating an increase in secretions necessary for fetal nutrition. Progesterone, like hCG, is necessary to prevent spontaneous abortion because it prevents contractions of the uterus, and is necessary for implantation.
Estrogen is a crucial hormone in the process of proliferation. This involves the enlargement of the breasts and uterus, allowing for growth of the fetus and production of milk. Estrogen is also responsible for increased blood supply towards the end of pregnancy through vasodilation. The levels of estrogen during pregnancy can increase so that they are thirty times what a non-pregnant woman mid-cycles estrogen level would be.
Human placental lactogen is a hormone used in pregnancy to develop fetal metabolism and general growth and development. Human placental lactogen works with Growth hormone to stimulate Insulin-like growth factor production and regulating intermediary metabolism. In the fetus, hPL acts on lactogenic receptors to modulate embryonic development, metabolism and stimulate production of IGF, insulin, surfactant and adrenocortical hormones. hPL values increase with multiple pregnancies, intact molar pregnancy, diabetes and Rh incompatibility. They are decreased with toxemia, choriocarcinoma, and Placental insufficiency.[21][22]

text: Cloaking from immune system of mother[edit]

text: The placenta and fetus may be regarded as a foreign allograft inside the mother, and thus must evade from attack by the mother's immune system.

text: For this purpose, the placenta uses several mechanisms:

text:
It secretes Neurokinin B-containing phosphocholine molecules. This is the same mechanism used by parasitic nematodes to avoid detection by the immune system of their host.[23]
There is presence of small lymphocytic suppressor cells in the fetus that inhibit maternal cytotoxic T cells by inhibiting the response to interleukin 2.[24]

text: However, the Placental barrier is not the sole means to evade the immune system, as foreign fetal cells also persist in the maternal circulation, on the other side of the placental barrier.[25]

text: Other functions[edit]

text: The placenta also provides a reservoir of blood for the fetus, delivering blood to it in case of hypotension and vice versa, comparable to a capacitor.[26]

text: Gene and protein expression[edit]

text: About 20,000 protein coding genes are expressed in human cells and 70% of these genes are expressed in the normal mature placenta.[27][28] Some 350 of these genes are more specifically expressed in the placenta and less than 100 genes are highly placenta specific. The corresponding specific proteins are mainly expressed in trophoblasts and have functions related to female pregnancy. Examples of proteins with elevated expression in placenta compared to other organs and tissues are PEG10 and the cancer testis antigen PAGE4 expressed in cytotrophoblasts, CSH1and KISS1 expressed in syncytiotrophoblasts, and PAPPA2 and PRG2 expressed in extravillous trophoblasts.

text: Clinical significance[edit]

text: Numerous pathologies can affect the placenta.

text:
Placenta accreta, when the placenta implants too deeply, all the way to the actual muscle of uterine wall (without penetrating it)
Placenta praevia, when the placement of the placenta is too close to or blocks the cervix
Placental abruption/abruptio placentae

text: Infections involving the placenta:

text:
Placentitis, such as the TORCH infections.
Chorioamnionitis.

text: Society and culture[edit]

text: The placenta often plays an important role in various cultures, with many societies conducting rituals regarding its disposal. In the Western world, the placenta is most often incinerated.[29]

text: Some cultures bury the placenta for various reasons. The Māori of New Zealand traditionally bury the placenta from a newborn child to emphasize the relationship between humans and the earth.[30] Likewise, the Navajo bury the placenta and umbilical cord at a specially chosen site,[31] particularly if the baby dies during birth.[32] In Cambodia and Costa Rica, burial of the placenta is believed to protect and ensure the health of the baby and the mother.[33] If a mother dies in childbirth, the Aymara of Bolivia bury the placenta in a secret place so that the mother's spirit will not return to claim her baby's life.[34]

text: The placenta is believed by some communities to have power over the lives of the baby or its parents. The Kwakiutl of British Columbia bury girls' placentas to give the girl skill in digging clams, and expose boys' placentas to ravens to encourage future prophetic visions. In Turkey, the proper disposal of the placenta and umbilical cord is believed to promote devoutness in the child later in life. In Ukraine, Transylvania, and Japan, interaction with a disposed placenta is thought to influence the parents' future fertility.

text: Several cultures believe the placenta to be or have been alive, often a relative of the baby. Nepalese think of the placenta as a friend of the baby; Malaysian Orang Asli regard it as the baby's older sibling.[33] Native Hawaiians believe that the placenta is a part of the baby, and traditionally plant it with a tree that can then grow alongside the child.[29] Various cultures in Indonesia, such as Javanese, believe that the placenta has a spirit and needs to be buried outside the family house.

text: In some cultures, the placenta is eaten, a practice known as placentophagy. In some eastern cultures, such as China, the dried placenta (ziheche 紫河車, literally "purple river cart") is thought to be a healthful restorative and is sometimes used in preparations of traditional Chinese medicine and various health products.[35] The practice of human placentophagy has become a more recent trend in western cultures and is not without controversy; its practice being considered cannibalism is debated.

text: Some cultures have alternative uses for placenta that include the manufacturing of cosmetics, pharmaceuticals and food.

text: Additional images[edit]

text:
Fetus of about 8 weeks, enclosed in the amnion. Magnified a little over two diameters.

Picture of freshly delivered placenta and umbilical cord wrapped around Kelly clamps

Fresh human placenta

Micrograph of a placental infection (CMV placentitis).

Micrograph of CMV placentitis.

A 3D Power doppler image of vasculature in 20-week placenta

Placenta held.

Schematic view of the placenta

Maternal side of a whole human placenta, just after birth

Fetal side of same placenta

Ziheche (紫河车), dried human placenta used in traditional Chinese medicine


document_title: Appendicular skeleton

question_text: the fibula is found in which region of the appendicular skeleton

text: Appendicular skeleton

text: Human structure[edit]

text: Of the 206 bones in the human skeleton, the appendicular skeleton comprises 126. Functionally it is involved in locomotion (lower limbs) of the axial skeleton and manipulation of objects in the environment (upper limbs).

text: The appendicular skeleton forms during development from cartilage, by the process of endochondral ossification.

text: The appendicular skeleton is divided into six major regions:

text:
Pectoral girdles (4 bones) - Left and right clavicle (2) and scapula (2).
Arms and forearms (6 bones) - Left and right humerus (2) (arm), ulna (2) and radius (2) (forearm).
Hands (54 bones) - Left and right carpals (16) (wrist), metacarpals (10), proximal phalanges (10), intermediate phalanges (8) and distal phalanges (10).
Pelvis (2 bones) - Left and right hip bone (2).
Thighs and legs (8 bones) - Left and right femur (2) (thigh), patella (2) (knee), tibia (2) and fibula (2) (leg).
Feet and ankles (52 bones) - Left and right tarsals (14) (ankle), metatarsals (10), proximal phalanges (10), intermediate phalanges (8) and distal phalanges (10).

tag: ol

text: It is important to realize that through anatomical variation it is common for the skeleton to have many accessory bones (sutural bones in the skull, cervical ribs, lumbar ribs and even extra lumbar vertebrae).

text: The appendicular skeleton of 126 bones and the axial skeleton of 80 bones together form the complete skeleton of 206 bones in the human body. Unlike the axial skeleton, the appendicular skeleton is unfused. This allows for a much greater range of motion.[2]

text: Additional images[edit]

text:
Appendicular skeleton (shown in red).

Illustration depicting anterior and posterior view of appendicular skeleton


document_title: The Great Indian Laughter Challenge

question_text: who won the great india laughter challenge 2017

text: The Great Indian Laughter Challenge

text: Seasons[edit]

text: In the first season, Sunil Pal was the winner, Ahsaan Qureshi was runner up and Raju Srivastava was second runner up. In the second season contestants from Pakistan were present and the winner Rauf Lala was from Pakistan. The third season was won by Kapil Sharma and the first runner up was Chandan Prabhakar both from Amritsar. Many other talented comedians like Siraj Khan, Sudesh Lehari, Rajiv Thakur, Bharti Singh, Navin Prabhakar, Jassi Kochar, Khayaali, Dipoo Srivastava, Ahsaan Qureshi have appeared in the show.

text: The first two seasons were followed by another show, The Great Indian Laughter Champions, which included top performers of the previous shows. Here also the judges were Sidhu and Shekar including some celebrity guests as well.

text: Recently the first woman to participate was Aarti Kandpal. The fourth season's finalists were Rasbihari Gaur, Bharti Singh, Suresh Albela, and a duo from Pakistan. The winner for the fourth season after a tough laughter war was Suresh Albela.

text: Season 5 had 3 mentors Zakir Khan, Hussain Dalal (Dialouge Writer)| Hussain Dalal and Mallika Dua later replaced by Sajid Khan and Shreyas Talpade who along with Akshay Kumar, will select 12 finalists who will compete for the title.

text: Season I[edit]

text:
Sunil Pal (Winner)
Ahsaan Qureshi (Runner-up)
Raju Srivastava
Naveen Prabhakar
Bhagwant Mann
Parag Kansara

text: Season II[edit]

text:
Rauf Lala (Winner)
Rajeev Nigam (Runner-up)
Khayali
Pratap Faujdar
Irfan Malik and Ali Hassan
Dr. Tushar Shah
Rajkumar Javkar
Saransh Bhardwaj (as a guest appearance)
Gaurav Jha

text: Season III[edit]

text:
Kapil Sharma (winner)
Chandan Prabhakar (Runner-up)
Sunil Pal
Aamil Keeyan Khan
Sudesh Lehri
Raju Srivastava

text: Season IV[edit]

text:
Suresh Albela (Winner)
Sikandar Sanam (Runner-up)
Wali Sheikh
Bharti Singh
Jaswant Singh
Rasbihari Gaur
Shrikant Maski
Ramdas Yeole
Rehan Jamlal
Sugandha Mishra
Vinod Rathore

text: Season V - 2017[edit]

text:
Abhishek Walia (Winner)
Nitesh Shetty (Runner up)
Parvindar Singh
Vishwas Chauhan
Vignesh Pandey
Shyam Rangeela
Jayvijay Sachan
Abhay Kumar
Sahil Bhatia
Mohammad Anas
Naman Jain
Sumit Sourav
Ajay Singh Chauhan
Gaurav Gupta