AniDB

I realize this is probably stupid but... Say I go to a page about an anime and I click on one of the episodes. I get another page (maybe like this http://anidb.info/perl-bin/animedb.pl?show=file&fid=269788) There's a bunch of numbers called CRC/Status, MD5 Hash, SHA1 Hash, TTH Hash and so on. Wh...