In the initial stages of development of Robotics, it was defined as "a mulitpurpose machine incorporating a memory and a mechanism intended to execute various functions automatically, thereby substituting for human manpower."
Almost all robots are comprised of a movable body, wheels operated by motors, and parts which can be moved made of plastic or metal. The sections are coupled together with joints. Solenoids and electric motors are used as actuators to operate the robots, while hydraulic and pneumatic systems are also utilized for this purpose. A combination of all these systems is also used.