Greek alphabet from which the later standard Greek alphabet emerged. Athens used a local form of the "light blue" alphabet type until the end of the fifth century BC, which lacked the letters Ξ and Ψ as well as the vowel symbols Η and Ω. In the Old Attic alphabet, stood for and for . was used for all three sounds (correspondinɡ to classical respectively), and was used for all of (corresponding to classical respectively). The letter (heta) was used for the consonant . Some variant local letter forms were also characteristic of Athenian writing, some of which were shared with the
The Alphabet Cipher The Alphabet Cipher Lewis Carroll published "The Alphabet-Cipher" in 1868, possibly in a children's magazine. It describes what is known as a Vigenère cipher, a well-known scheme in cryptography. While Carroll calls this cipher "unbreakable", Kasiski had published a volume describing how to break such ciphers from five years earlier, and Charles Babbage had secretly found ways to break polyalphabetic ciphers during the Crimean War. The piece begins with a tabula recta. ABCDEFGHIJKLMNOPQRSTUVWXYZ Each column of this table forms a dictionary of symbols representing the alphabet: thus, in the A column, the symbol is the same as the letter represented;