How can you tell if your copy of a game is good or bad? The Redump project can answer that, and here's how it works.
Every game has a digital fingerprint called a "hash" and when two files have the same hash you know they're exactly the same. The Redump project records the hashes of many videogames, so just compare your game's hash to the one in Redump and if they match, you have a good copy!
To guarantee the best games, each PS1 game at Vimm's Lair is scanned nightly with the latest Redump data. Why nightly? Well, Redump isn't perfect and mistakes can happen, so over time corrections are made and the hash changes. Those changes are flagged for review, so if you see a flagged game and know where to find the latest copy please lend a hand by posting it on the Message Board.