set-top box

A typical modern set-top box, along with its remote control - pictured here a digital terrestrial TV receiver by TEAC A set-top box (STB), also known as a cable box, receiver, or simply box, and historically television decoder or a converter, is an information appliance device that generally contains a TV tuner input and displays output to a television set, turning the source signal into content in a form that can then be displayed on the television screen or other display device. It is designed to be placed alongside or "on top" (hence the name) of a television set.

Set-top boxes are used in cable television, satellite television, terrestrial television and Internet Protocol television systems, as well as other uses such as digital media players ("streaming boxes"). Alternatives to set-top boxes are the smaller dongles, and television sets with built-in TV tuners.