A robot can be defined as a programmable, self-controlled device consisting of electronic, electrical, or mechanical units. More generally, it is a machine that functions in the place of a living agent. Robots are especially desirable for certain work functions because, unlike humans, they never get tired; they can endure physical conditions that are uncomfortable or even dangerous; they can operate in airless conditions; they do not get bored by repetition, and they cannot be distracted from the task at hand.

The concept of robots is a very old one yet the actual word robot was invented in the 20th century from the Czechoslovakian word robota or robotnik meaning an enslaved person, servant, or forced laborer. Robots don't have to look or act like humans but they do need to be flexible so they can perform different tasks.

Early industrial robots handled radioactive material in atomic labs and were called enslaver/enslaved person manipulators. They were connected together with mechanical linkages and steel cables. Remote arm manipulators can now be moved by push buttons, switches or joysticks.

Current robots have advanced sensory systems that process information and appear to function as if they have brains. Their "brain" is actually a form of computerized artificial intelligence (AI). AI allows a robot to perceive conditions and decide upon a course of action based on those conditions.

Components of Robots

Effectors — "arms," "legs," "hands," "feet"

Sensors — parts that act like senses and can detect objects or things like heat and light and convert the object information into symbols that computers understand

Computer — the brain that contains instructions called algorithms to control the robot

Equipment — this includes tools and mechanical fixtures

Characteristics that make robots different from regular machinery are that robots usually function by themselves, are sensitive to their environment, adapt to variations in the environment or to errors in prior performance, are task-oriented and often have the ability to try different methods to accomplish a task.

Common industrial robots are generally heavy rigid devices limited to manufacturing. They operate in precisely structured environments and perform single highly repetitive tasks under pre-programmed control. There were an estimated 720,000 industrial robots in 1998. Tele-operated robots are used in semi-structured environments such as undersea and nuclear facilities. They perform non-repetitive tasks and have limited real-time control.