The term 720p
refers to 720 lines of progressive
video (720 lines per frame). Higher resolution than standard DVD, which is 480i or 480p
. Usually refers to 1280×720 resolution in 1.78 aspect ratio. [Source: LG Guide to HDTV]
See also HDTV.
Also see Webopedia’s “Did You Know…All About Digital TV . DTV and HDTV“.