MD5的全稱是Message-digest Algorithm 5（信息-摘要算法），用于確保信息傳輸完整一致。在90年代初由MIT Laboratory for Computer Science和RSA Data Security Inc,的Ronald L. Rivest開發出來，經MD2、MD3和MD4發展而來。它的作用是讓大容量信息在用數字簽名軟件簽署私人密鑰前被"壓縮"成一種保密的格式（就是把一個任意長度的字節串變換成一定長的大整數）。
Enclosed in this distribution are four projects:
MD5DLLTest: Visual basic project which runs the MD5 test suite against a
MD5 DLL (see below).
VbMD5: A Visual Basic native MD5 message digest class based on the
RSA reference implementation.
md5DLL: A C project which generates a simple Win32 DLL with
the MD5 message digest routines using the RSA reference
implementation.
MD5Java: A Java implementation of the MD5 message digest algorithm based
on the RSA reference implmentation.
Let me know if this has any use!
Robert M. Hubley
hubley@u.washington.edu
