AZ - Allegiance Zone
Allegiance Zone was provided by Microsoft when they supported the game. It required a monthly subscription to play on, but had more factions and a statistics system. Large Zone Games were organised on the Allegiance Zone which affected the ongoing storyline of the Allegiance universe. Since paying customers were more dedicated, it also gained more experienced players.
FZ - Free Zone
The Merging of AZ and FZ
In July 2000 the Allegiance Zone was opened up to all players. This caused server overload and heavy lag, creating the opposite effect of what Microsoft wanted - it drove away more players. AZ went back to its pay-to-play status.
In June 2001 Microsoft dropped Allegiance. They removed player authentication (MSN Gaming Zone integration), Allegiance Zone and all its features, allowed Free Zone to use Belters and Rixian Unity, and bumped up the max server limit to 64 for Free Zone servers.
FAZ - Free Allegiance Zone
Since the release of the source code in Febuary 2004 the community took this name upon itself, endeavouring to bring back all the features of AZ, fix bugs, and create new features; while still retaining Allegiance as a free game.
MSN Gaming Zone
MSN Gaming Zone is a website dedicated to Microsoft games. It was used to publish background material on Allegiance, and post news items (archived here).
Other uses of the word Zone