Message Digest (hash) engine allows direct processing of arbitrary length messages using a variety of hashing algorithms.
MD2 is a weak algorithm invented in 1989, still used today in some public key cryptography.
MD5 is an extremely popular hashing algorithm but now has very well known collision issues. - md5 hash generator
Message digest functions also called hash functions , are used to produce digital summaries of information called message digests. Message digests (also called hashes) are commonly 128 bits to 160 bits in length and provide a digital identifier for each digital file or document. Message digest functions are mathematical functions that process information to produce a different message digest for each unique document.
A hash function is any function that can be used to map data of arbitrary size to data of fixed size. The values returned by a hash function are called hash values, hash codes, digests, or simply hashes.
Hash functions are profusely implemented in software. Applications written in C usually rely on OpenSSL routines, server-side security is coded in PHP or Java, and ASP.NET developers combine the cryptographic services of the .NET framework with powerful features of C# or Visual Basic. C++, Perl, Ruby and other programming languages have their own security APIs created as part of the standard library or as supplementary modules.
A message digest hash function is a cryptographic primitive used for digital signatures and password protection. It maps a message of arbitrary length to a fixed-length hash value or "message digest". The same input (message) will always result in the same output.