What is the difference between DTV, HDTV, and SDTV?
“DTV” is a general reference to Digital Television, as compared to “analog” Television. DTV broadcasts can be either HDTV (high-definition television) or SDTV (standard-definition television). HDTV can broadcast at resolutions typically as high as 1920 by 1080 pixels (2 million pixels), whereas the resolutions of SDTV broadcasts are typically only as high as 640 by 480 pixels (290,000 pixels).
In comparison, analog television produces a total of about 210,000 pixels. Broadcasters and cable providers can choose which format of DTV they transmit, and most DTV's and new HDTV set-top boxes will be able to receive the signal regardless of which format is transmitted. Note, however, that your standard analog TV set will not be able to receive DTV signals (neither HDTVnor SDTV).