input devices [4]![click to hear](/images/speaker.jpg)
Electronic devices used to transmit data and commands to a computer.
optical mouse ![click to hear](/images/speaker.jpg)
Mouse in which the ball is replaced by an optical system (light-emitting diode and sensor); it has no movable parts.
optical sensor ![click to hear](/images/speaker.jpg)
Device that measures the mouse’s movements by analyzing the light rays (emitted by a diode) reflected from its support surface.
wheel mouse ![click to hear](/images/speaker.jpg)
Mechanical or optical mouse that contains a scroll wheel.
cable ![click to hear](/images/speaker.jpg)
Flexible cable containing the conductors by which the mouse is attached to the computer.
cordless mouse ![click to hear](/images/speaker.jpg)
Mechanical or optical mouse connected to the computer by infrared or radio signals.