Battle Droid

B1s were perhaps the most numerous—and expendable—soldiers in galactic history, and, unlike most organic soldiers, they were capable of action in hostile environments like underwater or in space. They were designed, for the most part, to defeat their enemies through sheer numbers, not through their ability to think and utilize combat skills (unlike clone troopers).
The B1 Battle Droid was frequently used as a soldier for the Trade Federation. In almost every battle involving the Trade Federation there were battle droids.

Super Battle Droid

The B2 super battle droid (SBD) was an upgraded version of the B1 battle droid, with superior armament and armor. They were manufactured after the battle of Naboo proved need for stronger droids.

Droid Commando

The BX-series droid commando was an elite battle droid model made for stealth assignments