There are of course a wide range of cryptographic algorithms in use. The following are amongst the most well known:

**DES**

This is the 'Data Encryption Standard'. This is a cipher that operates on 64-bit blocks of data, using a 56-bit key. It is a 'private key' system. Further Details on the DES Algorithm

**RSA**

RSA is a public-key system designed by Rivest, Shamir, and Adleman. Further Details on the RSA Algorithm

**HASH**

A 'hash algorithm' is used for computing a condensed representation of a fixed length message/file. This is sometimes known as a 'message digest', or a 'fingerprint'..

**MD5**

MD5 is a 128 bit message digest function. It was developed by Ron Rivest. Further Details on the MD5 Algorithm

**AES**

This is the Advanced Encryption Standard (using the Rijndael block cipher) approved by NIST.

**SHA-1**

SHA-1 is a hashing algorithm similar in structure to MD5, but producing a digest of 160 bits (20 bytes).Because of the large digest size, it is less likely that two different messages will have the same SHA-1 message digest. For this reason SHA-1 is recommended in preference to MD5.

**HMAC**

HMAC is a hashing method that uses a key in conjunction with an algorithm such as MD5 or SHA-1. Thus one can refer to HMAC-MD5 and HMAC-SHA1.