DES
Data Encryption Standard
DES is an encryption method originally developed by IBM in the 1970s. Certified by the U.S. government for the transmission of any data that is not classified top-secret, DES uses an algorithm for private-key encryption, in which the sender uses the same private key to send the message that the recipient uses to decode it. The key consists of 56 bits of data, which are transformed and combined with each 64-bit block of the data to be sent. Though DES is fairly weak with only one iteration, repeating it using slightly different keys can provide excellent security.