Stands for "Digital Video Recorder." A DVR is basically a VCR that uses a hard drive instead of video tapes. It can be used to record, save, and play back television programs. Unlike a VCR, however, a DVR can also pause live TV by recording the current show in real time. The user can choose to fast forward (often during commercials) to return to live television.
Most satellite and cable TV companies offer a DVR as an option with their digital television packages. Since cable boxes already provide program listings through some kind of TV guide interface, most DVRs allow users to use the guide to schedule recordings. For example, a user can use the remote to search through the guide's program listings for the current week and select the shows he would like to record.
TiVo, the "brand name" DVR, performs the same functions as a DVR offered directly from a cable company. However, TiVo users can choose to buy the DVR box instead of renting it. Since TiVo is a standalone box, it does not require cable or satellite TV. While TiVo users who buy their own TiVo boxes may avoid the monthly rental fees, they must pay a monthly fee for program listings if they want to schedule recordings.
DVRs conveniently save shows in an list that the user can access at any time. Since the shows are stored on DVR's hard drive, there is no need to rewind or fast forward to play a certain show, like a VCR requires. While DVRs make it even easier to record your favorite shows every week or even every day, it also makes it easier to watch more TV. And an excuse to watch more TV is something most of us don't need.