AA (Alternate Amber) - It's Amber...sort of (i.e. Ambermaniacs).
EL (Elders) - Characters will be Elder Amberites from the books.
FF (Freeform) - A game run in near real time, does not have 'traditional' game structure.
KF (Kid Friendly) - Game is appropriate for younger players.
NA (Non-Amber Game) - Game does not take place in the Amber universe and is completely unrelated to Amber.
NC (New Campaign) - The start of a new game that will continue at future conventions, usually with the same players.
OC (Ongoing Campaign) - A continuing campaign played from year to year, usually with the same players.
SM (Seminar) - Event is a discussion of a specific topic, not a game.
SR (Series) - A series of separate, self-contained adventures, set in the same universe, often with different players.
SW (Shared World) - Characters are from existing or defunct campaigns but their histories are modified so that they are all part of the same universe and are usually familiar with each other.
TW (Throne War) - Everyone tries to kill each other or form alliances to attain a goal.
UC (Unique Characters) - Characters are created specifically for this game world, as opposed to being from existing or defunct campaigns.
XO (Crossover) - Characters are from existing or defunct campaigns and arrive from different universes with their history intact.