EaW Game Modes
There are three major modes of play in Empire at War
Campaign
This mode lets you play as the Empire or Rebellion in a story mode where you follow the birth of the Alliance and the events leading up to the Battle of Yavin
Galactic Conquest
This is a more free form mode, where you don't follow a story driven path. Instead, you vie for total control of the galaxy. You can play against the computer or against a friend
Skirmish Battles
Skirmish Battles let you attempt a land or space map (or both) without the added galactic conquest. This allows you to jump in quickly and play against a friend, without having to conquer the entire galaxy