Atbash
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Atbash is a simple substitution cipher for the Hebrew alphabet. It consists of substituting aleph (the first letter) for tav (the last), beth (the second) for shin (one before last), and so on, reversing the alphabet. A couple of words in the Book of Jeremiah, Leb Kamai and Sheshakh, are atbash for Kasdim/Kasdin (Chaldeans) and Babel respectively, probably written thus (Jer. 25:26; 51:1, 41). It has been associated with the esoteric methodologies of Jewish mysticism's interpretations of Hebrew religious texts as in the Kabbalah.
An atbash cipher for the Roman alphabet would be as follows:
Plain: abcdefghijklmnopqrstuvwxyz Cipher: ZYXWVUTSRQPONMLKJIHGFEDCBA
Atbash can also be used to mean the same thing in any other alphabet as well. This is a very simplistic substitution cipher.
For example, in Atbash, the letters "nlmvb" indicate the word "money".
A few English words 'Atbash' into other English words. For example, "hob"="sly", "hold"="slow", "holy"="slob", "horn"="slim", "irk"="rip" and "low"="old". There are many more, such as "glow"="told", "grog"="tilt", and "horn"="slim" which may be readily found with simple scripts such as:
perl -w -e 'foreach $firstRef (["a" .. "z"], ["A" .. "Z"]) { @first = @$firstRef; foreach $i (0..$#first) { $subst {$first [$i]} = $first [$#first - $i]; }; } @words = <>; foreach $word (@words) { chomp $word; $known {$word} = 1; } foreach $word (keys %known) { @word = split "", $word; @newword = (); foreach $character (@word) { $subst {$character} = $character unless defined $subst {$character}; push @newword, $subst {$character}; } $newword = join "", @newword; print "$word $newword\n" if defined $known {$newword} and length $word > 1; }' /usr/share/dict/words
It is a very weak cipher because it only has one possible key, and it is a simple monoalphabetic substitution cipher. However, this may not have been an issue in the cipher's time.
The Atbash cipher is referenced in Google's Da Vinci Code Quest, in which participants must decode a common word from Atbash.
The @ symbol is known in French, among other things, as "at" bâclé. This seems to be a deliberate pun on "atbash clé" - i.e. A secret message is set to use the atbash cipher at this point in reading the document.
[edit] See also
[edit] External links
- Javascript online encrypter/decrypter for Atbash
- MS-DOS software for encrypting and decrypting with Atbash
- Atbash as discussed on The Beginner's Guide to Cryptography
- An online encrypter/decrypter for Atbash
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