CRC32 Static Library for Microsoft VC++ was produced to make your CRC checking operations quick & easy to implement seamlessly without the need for an external DLL The CRC is a "digital fingerprint" of a file, With CRC32 you can "melt down" a huge 20 MB (or even much bigger) file to have a small, handy reference to it, a single 32-bit number like 7d9c42fb (hexadecimal notation) which would unambiguously reflect the entire contents of this huge file. Now if some changes to this file happened, no matter how small, maybe only a single wrong bit somewhere in the middle, a new CRC-32 calculation would yield a completely different reference number (say 3faa83bd). So there