Digital television (DTV) is a new type of broadcasting technology that will transform television as we now know it. By transmitting the information used to make a TV picture and sound as "data bits" (like a computer), a digital broadcaster can carry more information than is currently possible with analog broadcast technology.
For example, the technology allows the transmission of pictures with higher resolution for dramatically better picture and sound quality than currently available – called High Definition Television (HDTV) - or the transmission of several "standard definition" TV programs at once – called “multicasting.” "Standard definition" digital TV pictures would be similar in clarity and detail to the best TV pictures being received and displayed today using the current analog broadcast system and TV receivers.
DTV technology can also be used to provide interactive video and data services that are not possible with “analog” technology.
Source: http://www.dtv.gov
