Source : Webster's Revised Unabridged Dictionary (1913)

Cryptography \Cryp*tog"ra*phy\ (-f?), n. [Cf. F. cryptographie.]
   The act or art of writing in secret characters; also, secret
   characters, or cipher.

Source : WordNet®

cryptography
     n 1: the science of analyzing and deciphering codes and ciphers
          and cryptograms [syn: {cryptanalysis}, {cryptanalytics},
           {cryptology}]
     2: act of writing in code or cipher [syn: {coding}, {secret
        writing}]

Source : Free On-Line Dictionary of Computing

cryptography
     
         The practise and study of {encryption} and
        {decryption} - encoding data so that it can only be decoded by
        specific individuals.  A system for encrypting and decrypting
        data is a cryptosystem.  These usually involve an {algorithm}
        for combining the original data ("{plaintext}") with one or
        more "keys" - numbers or strings of characters known only to
        the sender and/or recipient.  The resulting output is known as
        "{ciphertext}".
     
        The security of a cryptosystem usually depends on the secrecy
        of (some of) the keys rather than with the supposed secrecy of
        the {algorithm}.  A strong cryptosystem has a large range of
        possible keys so that it is not possible to just try all
        possible keys (a "{brute force}" approach).  A strong
        cryptosystem will produce ciphertext which appears random to
        all standard statistical tests.  A strong cryptosystem will
        resist all known previous methods for breaking codes
        ("{cryptanalysis}").
     
        See also {cryptology}, {public-key encryption}, {RSA}.
     
        {Usenet} newsgroups: {news:sci.crypt},
        {news:sci.crypt.research}.
     
        {FAQ} {MIT
        (ftp://rtfm.mit.edu/pub/usenet/news.answers/cryptography-faq/)}.
     
        {Cryptography glossary
        (http://www.io.com/~ritter/GLOSSARY.HTM#BruteForceAttack)}.
     
        {RSA cryptography glossary
        (http://www.rsasecurity.com/rsalabs/faq/glossary.html)}.
     
        {Cryptography, PGP, and Your Privacy
        (http://draco.centerline.com:8080/~franl/crypto.html)}.
     
        (2000-01-16)