For those fans of Halo and Halo 2, or even of the Myth series of RTS games, that aren't familiar with Bungie's version of ancient history, also known as the 1990s, Inside Mac Games has put up a Marathon Primer, and the denizens of the Marathon Story Page are already picking it to pieces looking for small errors and omissions.

Thanks to ukimalefu who posted the initial link the Marathon Story Forum.