High Definition TV (HDTV) HDTV in widescreen provides the highest resolution and picture quality of all DTV formats. A current analog TV picture is made up of 480 horizontal lines. An HDTV picture can have up to 1080 lines, allowing for sharp picture detail. The most common formats are 720p (“p” stands for progressive scan) and 1080i (“i” stands for interlaced).

Enhanced Definition TV (EDTV) EDTV is a step up from analog TV and SDTV. Also called 480 progressive (480p), EDTV can be 16x9 or 4x3 format and provides better picture quality than SDTV, but not as good as HDTV. Most DVDs are encoded as 480p.

Standard Definition TV (SDTV) SDTV is the baseline display and resolution for both analog and digital TVs. Transmission of SDTV is usually in the traditional 4x3 aspect ratio, but may be wide-screen 16x9. SDTV and analog TV can deliver up to 480 interlaced (480i) resolution, although analog TV may be lower.