[The Xerox Alto] was first introduced in 1973, at a time when that same Xerox meant only “photocopy”, and IBM was an extremely important PC manufacturer; among all the features it had, what is probably its most influential achievement is that it was purposely built to run a GUI operating system, the Alto Operating System, at a time when something like that was unheard of. […] The first Alto game we’ll quickly mention is called MazeWar; it wasn’t originally released for this computer, but it was instead ported from another computer called Imlac, which featured intriguing vector-based graphics. What was special about this game is that, just like Alto Trek, it was a multiplayer game, and could be played against people on the same network; luckily for the busy researchers of PARC, it was easy to jump in and out of the game without disturbing anyone, as each instance of it ran on every Alto independently, and it would connect to the network only when it needed to exchange data with other players (so, for instance, the person who started the game, the host, could leave at any time, and the MazeWar match would simply continue).[…] Link