Experience point

EXP (Experience Points) are awarded to players based on their performance in a Halo 3 multiplayer match. Along with skill, EXP determines a player's rank and advancement in rank. Points are awarded thusly :
 * Win: 1 EXP
 * Loss: 0 EXP
 * Quitting/Disconnecting from the Match Early: -1 EXP

EXP is only lost when a player leaves a match before it is over. This penalty typically only applies to team matches, in any playlist. Also, the game counts a disconnect as quitting, so if your internet connection dropped or if you unplug your router, and even if in the unlikely event of a power outage, you will still be penalized as if you had quit the match through the menu.

In a free-for-all match, a player is considered to have won if he finishes in the top half; as in a team match, a player wins if his team wins.