The expanded form of HDTV is High Definition TV. This invention was originally introduced in the US in the 1990s, by the Digital HDTV Grand Alliance. This is referred as 1080 active lines, 16 x 9 aspect ratio in ITU-R BT.709.

High defintion TV conveys the meaning that presentation of big screen picture with more refinement and quality than available in usual analog TVs, or other digitalized television formats. However it is the highest quality Digital Television (DTV) display format available.

Rear screen, direct-view, plasma, and front screen projection are diverse varities of HDTVs displays. It is not viable to watch High defintion TV without 1080i HDTV tuner which is highly definite.