Electronic system for transmitting still or moving images and sound to receivers that project a view of the images on a picture tube or screen and recreate the sound.
Early versions (1900–20) of the cable TV systems (introduced in the 1960s), and recording or playback machines (in the 1980s; see {{link=VCR">VCR ) followed. Digital high-definition (HDTV) systems (1990s) provide sharper, clearer pictures and sound with little interference or other imperfections and have the potential to merge TV functions with those of computers.