High-definition television

High-definition television (HD) describes a television system providing a substantially higher image resolution than the previous generation of technologies. The term has been used since 1936,[1] but in modern times[when?] refers to the generation following standard-definition television (SDTV), often abbreviated to HDTV or HD-TV. It is the current de facto standard video format used in most broadcasts: terrestrial broadcast television, cable television, satellite television and Blu-ray Discs.