Battle Droid

Battle Droids (sometimes known as B1 Battle Droids) are the robotic foot soldiers of the Seperatists. They were mostly destroyed during the rise of the Empire, leaving very few left in the galaxy. The droids that where left where destroyed by the Empire on Mustafar. They are made out of common Tan robot pieces, but they always appear with a unique head depicting the Battle Droid's face. They could not hold a gun properly until 2007, when the turned Droid arm was created. They are now the most common Lego Starwars Minifigure ever, appearing in over 24 sets ad counting.

First Battle Droids
The very first Battle Droids appeared with the same pieces, with two sideways arms, a tan torso, and its normal head and legs, but it had a tan 1X2 Plate attached to a stud on its back to take the form of a backpack. These variants have appeared in 3343 Star Wars #4 and 7121 Naboo Swamp.

No Backpack
Battle Droids soon were rereleased in 7126 Battle Droid Carrier without backpacks. These were a very common variant until 2007. Like its previous variant, it could not hold a gun the right way.

Straight Arm
Battle Droids held guns straight in 2007 when they finally got straight arms to hold their blasters right. They were first introduced in the third version of Trade Federation MTT. The other arm of them is the old one that coould not hold guns right.

Two Turned Arms
In the Droid Gunship set, two Battle Droids feature two turned arms for an unknown reason.

Versions
Security Battle Droid

Pilot Battle Droid

Rocket Battle Droid

Rocket Battle Droid Commander

Battle Droid Commander

Super Battle Droid

Geonosian Battle Droid