Standard Definition TV (SDTV) – SDTV is the basic level of quality display and resolution for both analog and digital. Transmission of SDTV may be in either the traditional (4:3) or widescreen (16:9) format.
Enhanced Definition TV (EDTV) – EDTV is a step up from Analog Television. EDTV comes in 480p widescreen (16:9) or traditional (4:3) format and provides better picture quality than SDTV, but not as high as HDTV.
High Definition TV (HDTV) – HDTV in widescreen format (16:9) has the greatest picture quality of all digital broadcast formats. Combined with digitally enhanced sound technology, HDTV sets new standards for sound and picture quality in television.