What kind of TV format is 720i?

Answer 1

720i is an erroneous term found in numerous sources and publications. Typically it is a typo in which the author is referring to the 720p HDTV (high-definition television) format. However in some cases it is presented as an actual alternative format to 720p. In fact, no proposed or existing broadcast standard permits 720 interlaced lines in a video frame at any frame rate.