The Battle Droid is the foot soldier for the Trade Federation Droid Army. Battle Droids overwhelm Trade Federation enemies through co-ordinated tactics and sheer force of numbers. These emotionless droids cannot be pleaded with, bribed or be swayed by any other tactics. The reason for the Battle Droid's lack of emotion is due to its lack of cognitive functions. They are programmed to operate in virtually in any combat condition, however, they must receive the broadcast signals from the Droid Control Ship in order to function properly.

    The Battle Droid's head lacks any type of brain or central processor, instead it contains a large and sensitive signal receiver. The Battle Droid's small processors collect movement and limited sensory data which can be sent back to the Droid Control Ship. However, Battle Droids are incapable of independent thought, reaction or learning from their experiences. In addition they have poor firing accuracy and solely rely on the attack commands sent by the Droid Control Ship. Battle Droids are pre-programmed with basic functions, but virtually take all commands from the Droid Control Ship or a Command Officer Battle Droid. The droid seems to move fluidly since its movement commands were derived from pre-digitized motion-captured data taken from living soldiers. This data is broadcasted to each droid by the Central Control Computer onboard the Droid Control Ship.

    In an attempt to make the droid to appear menacing, the Battle Droid's designers modelled them after dead Neimoidian remains. When a Neimoidian body is left to rot, the brain mantle dehydrates, becoming dried sacs near the top of the skull, while the face stretches and warps. As a result, the rotted carcass of a Neimoidian strongly resembles that of the Battle Droid's features. The vile image of death that is presented by these droids gives them their skull husk heads, imitation brain sacs, bone like arms, dried cartilage-shaped shin plates and its other frightening features. The droids come equipped with generic feet which can be replaced with claws or pads if the situation warrants it. Contained in the top of the head of the Battle Droid is the general command storage. The left brain sac contains a specialized movement processor, while the right brain sac contains sampled movement cycle memory. While near to the nose of the droid's head is its vocoder and speech processor.

    The Battle Droids were designed to fold up tightly to take up minimum volume, which would allow more efficient storage of the droids. To increase efficiency, the droids were pre-programmed with specialized subroutines which break the droids down into four different types. Those types are Infantry, Pilot, Security and Command Officer. Command Officer Droids lead other Battle Droids into combat by relaying messages to other Battle Droids directly from the Droid Control Ship. Command Officer Droids receive their orders and signals via high-security priority channels. The reason that Command Officer Battle Droids exist is to streamline communication between Trade Federation officials and their Battle Droids. Pilot Droids are capable of piloting virtually every craft in the Trade Federation, including Battleships, AATs and MTTs. They are rarely fitted with backpacks of any kind. Security Droids are never fitted with backpacks, their duties includes: patrolling Trade Federation installations, guarding prisoners and protecting Neimoidian officials.