In cryptanalysis, a crib is a sample of known plaintext; the term originated at Bletchley Park, the British codebreaking operation during World War II (WWII). Cryptanalysis (from the Greek kryptós, hidden, and analýein, to loosen or to untie) is the study of methods for obtaining the meaning of encrypted information, without access to the secret information which is normally required to do so. ... The known-plaintext attack is a cryptanalytic attack in which the attacker has samples of both the plaintext and its encrypted version (ciphertext) and is at liberty to make use of them to reveal further secret information; typically this is the secret key. ... During World War II, British and American cryptographers at Bletchley Park broke a large number of Axis codes and ciphers, including the German Enigma machine. ... Combatants Allies: • Soviet Union, • UK & Commonwealth, • USA, • France/Free France, • China, • Poland, • ...and others Axis: • Germany, • Japan, • Italy, • ...and others Casualties Military dead: 18 million Civilian dead: 33 million Full list Military dead: 7 million Civilian dead: 4 million Full list World War II, also known as the Second World...

Their usage was adapted from the term meaning a bit of a cheat, for example, "I cribbed my answer from your test paper". The original sense of a "crib" was a literal or interlinear translation of a foreign language text — usually a Latin or Greek text — that students were likely to be assigned in the original language. Translation is an activity comprising the interpretation of the meaning of a text in one language — the source text — and the production, in another language, of a new, equivalent text — the target text, or translation. ... Latin is an ancient Indo-European language originally spoken in the region around Rome called Latium. ...

Examples include stereotyped salutations, endings, titles, routing codes, etc. In the case of WWII German traffic, one site regularly reported to headquarters each morning using precisely the same phrase, albeit encyphered using the current Enigma key. Combatants Allies: • Soviet Union, • UK & Commonwealth, • USA, • France/Free France, • China, • Poland, • ...and others Axis: • Germany, • Japan, • Italy, • ...and others Casualties Military dead: 18 million Civilian dead: 33 million Full list Military dead: 7 million Civilian dead: 4 million Full list World War II, also known as the Second World...

Bletchley Park sometimes arranged operations to provoke messages from the Germans to which they knew the plaintext; this was termed gardening. In cryptanalysis, gardening was a term used at Bletchley Park during World War II for schemes to entice the Germans to include known plaintext, which they called cribs, in their encrypted messages. ...