Before a game goes off to be duplicated, it goes through several stages and the first (generally, though the lines are blurred) playable version of a game is called the Alpha version. The Alpha, or for some companies, the pre-Alpha, gives people a chance to see how the game's engine is working and what the graphics are like. The Alpha will be bugged to hell, will crash and will probably not have the correct game physics but it will demonstrate certain aspects of the game.

After that producers, marketing-types and programmers hold lengthy discussions regarding the future direction of the game. When that's decided, a few more months of work ensues, and eventually the programmers come back with the next version of the game: the Beta.

The Beta version is much more stable, will have most of the game elements and should be playable. Tweaking will still be going on in the background, but it's the Beta version of a game that most magazines get to look at when it comes to previewing a game. Magazines are told (generally) what areas are being improved and what changes are likely to be made but for all intents and purposes the Beta version is an unplaytested version of the game that's going to be duplicated. It's rare that major gameplay elements are added or taken out of the Beta version.

Finally, once the programmers are happy with the code (well, once they've been told not to spend any more time on the project) a Master is produced and this is what becomes duplicated. It's usually after this process that the world and his wife start to notice all the bugs that have been missed.