A robot is provided which comprises a body unit, plural component units connected to the body unit, a memory mounted on the body unit for storing unit information of each of the component units and a basic operation program, a control unit mounted on the body unit for controlling the action of the robot, and a memory unit detachably mounted on the body unit for storing application program of the robot. The control unit reads out (i) the unit information, (ii) the basic operation program and (iii) the application program, and controls the component units in accordance with the read unit information, basic program, and application program.