Battle Droids were a robot programmed to obey orders and to weild guns with confidence, destroying the enemy forces. Unlike the Clone Troopers, Battle Doids were designed to have strength in numbers. Their were many types of Battle Droids including- Super Droids, Normal Droids, Droideka's and much more.

The Battle Droids first appearence was in Episode I. The Trade Fedreation, who eventually became Sepratists, raised an army of Battle Droids and invaded Naboo. They were unsuccessful when their Battle Station that controlled the droids was destroyed by a young boy, Anakin Skywalker. 

Another army was raised on Geonsis for the Sepratists. They were attacked by the Republic's new army, destroying many units. Mot long after, the remaining droids were destroyed at order 66 after Count Dooku's and General Grevious' death. 

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II

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III