remote control

In electronics, a remote control or clicker is an electronic device used to operate another device from a distance, usually wirelessly. For example, in consumer electronics, a remote control can be used to operate devices such as a television set, DVD player or other home appliance, from a short distance. A remote control is primarily a convenience feature for the user, and can allow operation of devices that are out of convenient reach for direct operation of controls. In some cases, remote controls allow a person to operate a device that they otherwise would not be able to reach, as when a garage door opener is triggered from outside or when a Digital Light Processing projector that is mounted on a high ceiling is controlled by a person from the floor level.
Early television remote controls (1956–1977) used ultrasonic tones. Present-day remote controls are commonly consumer infrared devices which send digitally-coded pulses of infrared radiation to control functions such as power, volume, channels, playback, track change, heat, fan speed, or other features varying from device to device. Remote controls for these devices are usually small wireless handheld objects with an array of buttons for adjusting various settings such as television channel, track number, and volume. For many devices, the remote control contains all the function controls while the controlled device itself has only a handful of essential primary controls. The remote control code, and thus the required remote control device, is usually specific to a product line, but there are universal remotes, which emulate the remote control made for most major brand devices.
Remote control in the 2000s includes Bluetooth connectivity, motion sensor-enabled capabilities and voice control.

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