Codetext
In cryptology, a code is a method used to Encryption, encrypt a message that operates at the level of meaning; that is, words or phrases are converted into something else. A code might transform "change" into "CVGDK" or "cocktail lounge". The U.S. National Security Agency defined a code as "A substitution cryptosystem in which the plaintext elements are primarily words, phrases, or sentences, and the code equivalents (called "code groups") typically consist of letters or digits (or both) in otherwise meaningless combinations of identical length."A History of U.S. Communications Security; the David G. Boak Lectures , National Security Agency (NSA), Volumes I, 1973, Volumes II 1981, partially released 2008, additional portions declassified October 14, 201 ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Ciphers
In cryptography, a cipher (or cypher) is an algorithm for performing encryption or decryption—a series of well-defined steps that can be followed as a procedure. An alternative, less common term is ''encipherment''. To encipher or encode is to convert information into cipher or code. In common parlance, "cipher" is synonymous with "code (cryptography), code", as they are both a set of steps that encrypt a message; however, the concepts are distinct in cryptography, especially classical cryptography. Codes generally substitute different length strings of characters in the output, while ciphers generally substitute the same number of characters as are input. A code maps one meaning with another. Words and phrases can be coded as letters or numbers. Codes typically have direct meaning from input to key. Codes primarily function to save time. Ciphers are algorithmic. The given input must follow the cipher's process to be solved. Ciphers are commonly used to encrypt written info ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Cryptanalysis
Cryptanalysis (from the Greek ''kryptós'', "hidden", and ''analýein'', "to analyze") refers to the process of analyzing information systems in order to understand hidden aspects of the systems. Cryptanalysis is used to breach cryptographic security systems and gain access to the contents of encrypted messages, even if the cryptographic key is unknown. In addition to mathematical analysis of cryptographic algorithms, cryptanalysis includes the study of side-channel attacks that do not target weaknesses in the cryptographic algorithms themselves, but instead exploit weaknesses in their implementation. Even though the goal has been the same, the methods and techniques of cryptanalysis have changed drastically through the history of cryptography, adapting to increasing cryptographic complexity, ranging from the pen-and-paper methods of the past, through machines like the British Bombes and Colossus computers at Bletchley Park in World War II, to the mathematically advanced ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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World War II
World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the world's countries participated, with many nations mobilising all resources in pursuit of total war. Tanks in World War II, Tanks and Air warfare of World War II, aircraft played major roles, enabling the strategic bombing of cities and delivery of the Atomic bombings of Hiroshima and Nagasaki, first and only nuclear weapons ever used in war. World War II is the List of wars by death toll, deadliest conflict in history, causing World War II casualties, the death of 70 to 85 million people, more than half of whom were civilians. Millions died in genocides, including the Holocaust, and by massacres, starvation, and disease. After the Allied victory, Allied-occupied Germany, Germany, Allied-occupied Austria, Austria, Occupation of Japan, Japan, a ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Leslie Groves
Leslie Richard Groves Jr. (17 August 1896 – 13 July 1970) was a United States Army Corps of Engineers officer who oversaw the construction of the Pentagon and directed the Manhattan Project, a Classified information#Top_Secret_(TS), top secret research project that developed the atomic bomb during World War II. The son of a Chaplain Corps (United States Army), U.S. Army chaplain, Groves lived at various Army posts during his childhood. In 1918, he graduated fourth in his class at the United States Military Academy at West Point, New York, West Point and was commissioned into the United States Army Corps of Engineers. In 1929, he went to Nicaragua as part of an expedition to conduct a survey for the Inter-Oceanic Nicaragua Canal. Following the 1931 Nicaragua earthquake, 1931 Nicaraguan earthquake, Groves took over Managua's water supply system, for which he was awarded the Nicaraguan Presidential Medal of Merit. He attended the Command and General Staff School at Fort Leavenw ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Atomic Bomb
A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission (fission or atomic bomb) or a combination of fission and fusion reactions (thermonuclear weapon), producing a nuclear explosion. Both bomb types release large quantities of energy from relatively small amounts of matter. Nuclear bombs have had yields between 10 tons (the W54) and 50 megatons for the Tsar Bomba (see TNT equivalent). Yields in the low kilotons can devastate cities. A thermonuclear weapon weighing as little as can release energy equal to more than 1.2 megatons of TNT (5.0 PJ). Apart from the blast, effects of nuclear weapons include firestorms, extreme heat and ionizing radiation, radioactive nuclear fallout, an electromagnetic pulse, and a radar blackout. The first nuclear weapons were developed by the Allied Manhattan Project during World War II. Their production continues to require a large scientific and industrial complex, primari ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Trinity Test
Trinity was the first detonation of a nuclear weapon, conducted by the United States Army at 5:29 a.m. MWT (11:29:21 GMT) on July 16, 1945, as part of the Manhattan Project. The test was of an implosion-design plutonium bomb, or "gadget", of the same design as the Fat Man bomb later detonated over Nagasaki, Japan, on August 9, 1945. Concerns about whether the complex Fat Man design would work led to a decision to conduct the first nuclear test. The code name "Trinity" was assigned by J. Robert Oppenheimer, the director of the Los Alamos Laboratory, possibly inspired by the poetry of John Donne. The test, both planned and directed by Kenneth Bainbridge, was conducted in the Jornada del Muerto desert about southeast of Socorro, New Mexico, on what was the Alamogordo Bombing and Gunnery Range (renamed the White Sands Proving Ground just before the test). The only structures originally in the immediate vicinity were the McDonald Ranch House and its ancillary buildin ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Joseph Stalin
Joseph Vissarionovich Stalin (born Dzhugashvili; 5 March 1953) was a Soviet politician and revolutionary who led the Soviet Union from 1924 until Death and state funeral of Joseph Stalin, his death in 1953. He held power as General Secretary of the Communist Party of the Soviet Union, General Secretary of the Communist Party from 1922 to 1952 and as the fourth Premier of the Soviet Union, premier from 1941 until his death. He initially governed as part of a Collective leadership in the Soviet Union, collective leadership, but Joseph Stalin's rise to power, consolidated power to become an absolute dictator by the 1930s. Stalin codified the party's official interpretation of Marxism as Marxism–Leninism, while the totalitarian political system he created is known as Stalinism. Born into a poor Georgian family in Gori, Georgia, Gori, Russian Empire, Stalin attended the Tiflis Theological Seminary before joining the Marxist Russian Social Democratic Labour Party. He raised f ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Harry Truman
Harry S. Truman (May 8, 1884December 26, 1972) was the 33rd president of the United States, serving from 1945 to 1953. As the 34th vice president in 1945, he assumed the presidency upon the death of Franklin D. Roosevelt that year. Subsequently, Truman implemented the Marshall Plan in the aftermath of World War II to rebuild the economy of Western Europe, and established both the Truman Doctrine and NATO to contain the expansion of Soviet communism. A member of the Democratic Party, he proposed numerous New Deal coalition liberal domestic reforms, but few were enacted by the conservative coalition that dominated the United States Congress. Truman was raised in Independence, Missouri, and during World War I fought in France as a captain in the Field Artillery. Returning home, he opened a haberdashery in Kansas City, Missouri, and was elected as a judge of Jackson County in 1922. Truman was elected to the U.S. Senate for Missouri in 1934. Between 1940 and 1944, he ga ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Spanish Civil War
The Spanish Civil War () was a military conflict fought from 1936 to 1939 between the Republican faction (Spanish Civil War), Republicans and the Nationalist faction (Spanish Civil War), Nationalists. Republicans were loyal to the Left-wing politics, left-leaning Popular Front (Spain), Popular Front government of the Second Spanish Republic. The opposing Nationalists were an alliance of Falangism, Falangists, monarchists, conservatives, and Traditionalism (Spain), traditionalists led by a National Defense Junta, military junta among whom General Francisco Franco quickly achieved a preponderant role. Due to the international Interwar period#Great Depression, political climate at the time, the war was variously viewed as class struggle, a War of religion, religious struggle, or a struggle between dictatorship and Republicanism, republican democracy, between revolution and counterrevolution, or between fascism and communism. The Nationalists won the war, which ended in early 1939, ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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D-day
The Normandy landings were the landing operations and associated airborne operations on 6 June 1944 of the Allied invasion of Normandy in Operation Overlord during the Second World War. Codenamed Operation Neptune and often referred to as D-Day (after the military term), it is the largest seaborne invasion in history. The operation began the liberation of France, and the rest of Western Europe, and laid the foundations of the Allied victory on the Western Front. Planning for the operation began in 1943. In the months leading up to the invasion, the Allies conducted a substantial military deception, codenamed Operation Bodyguard, to mislead the Germans as to the date and location of the main Allied landings. The weather on the day selected for D-Day was not ideal, and the operation had to be delayed 24 hours; a further postponement would have meant a delay of at least two weeks, as the planners had requirements for the phase of the moon, the tides, and time of day, that ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |