The demo features an interactive tutorial which gets you up to speed on important game concepts that will be necessary if you want to succeed. Once you're finished with the tutorial (or have skipped it) you can take command of the Rebel forces on Hoth, in a battle for control of the Outer Rim in the Vergesso Asteroids and try to free Tatooine from the grip of the Empire.
Han Solo and Chewbacca in the Millennium Falcon will lead your space fleet as you face off against the Tie Fighters, Star Destroyers and Boba Fett. You can download the 750MB demo over at 3D Gamers.
Empire at War is the first Star Wars game to give you the power to command an entire war in the Star Wars Galaxy, in battles between Imperial and Rebel forces. The RTS features both space and land combat, with more than 40 locations to battle in. The game is due for release on the PC in February 2006.