In cryptography, a Caesar cipher is one of the simplest and most
well-known classical encryption techniques. It is a type of
substitution cipher in which each letter in the plaintext is replaced
by a letter some fixed number of positions further down the alphabet.
For example, with a shift of 3, A would be replaced by D, B would
become E, and so on. The method is named after Julius Caesar, who
used it to communicate with his generals. The encryption step
performed by a Caesar cipher is often incorporated as part of more
complex schemes, such as the Vigenère cipher, and still has modern
application in the ROT13 system. As for all single alphabet
substitution ciphers, the Caesar cipher is easily broken and in
practice offers no communication security.
Read the rest of this article:
http://en.wikipedia.org/wiki/Caesar_cipher
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Today's selected anniversaries:
467:
Anthemius became Emperor of the Western Roman Empire.
(
http://en.wikipedia.org/wiki/Anthemius)
1633:
The formal interrogation of Galileo Galilei by the Inquisition began.
(
http://en.wikipedia.org/wiki/Galileo_Galilei)
1961:
Soviet cosmonaut Yuri Gagarin became the first man to enter outer
space.
(
http://en.wikipedia.org/wiki/Yuri_Gagarin)
1980:
Terry Fox dipped his artificial leg in the Atlantic Ocean and began
his trans-Canada run towards the Pacific Ocean to raise money for
cancer research.
(
http://en.wikipedia.org/wiki/Terry_Fox)
1981:
Columbia, the first space shuttle, was launched for its first flight.
(
http://en.wikipedia.org/wiki/Space_Shuttle_Columbia)
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Wikiquote of the day:
"A living body is not merely an integration of limbs and flesh but it
is the abode of the soul which potentially has perfect perception,
perfect knowledge, perfect power, and perfect bliss." -- Mahavira
(
http://en.wikiquote.org/wiki/Mahavira)