"A reprogrammable, multifunctional manipulator designed to move material, parts, tools, or specialized devices through various programmed motions for the performance of a variety of tasks".

A more inspiring definition can be found in Webster. According to Webster a robot is:
"An automatic device that performs functions normally ascribed to humans or a machine in the form of a human."

The benefits of robots to industry include improved management control and productivity and consistently high quality products. Industrial robots can work tirelessly night and day on an assembly line without an loss in performance.   More detail...