A personal video recorder (PVR) is an interactive TV recording device, in essence a sophisticated set-top box with recording capability (although it is not necessarily kept on top of the television set). Vendors and media also refer to the units by these names: digital video recorder (DVR); personal TV receiver (PTR); personal video station (PVS); and hard disk recorder (HDR).
Like the familiar VCR, a PVR records and plays back television programs, but, unlike the VCR, it stores the programs in digital (rather than analog) form. Like a VCR, a PVR has the ability to pause, rewind, stop, or fast-forward a recorded program. Because the PVR can record a program and replay it almost immediately with a slight time lag, what seem to be live programs can be manipulated as though they were recorded programs (which they actually are). A PVR's capabilities include time marking, indexing, and non-linear editing. The PVR encodes an incoming video data stream as MPEG-1 or MPEG-2 and stores it on a hard disk within a device that looks much like a VCR.
Most PVRs come as part of a subscriber service that may or may not charge a monthly fee. The service enables such activities as searching for shows according to type (movies or baseball games, for example), choosing among video-on-demand (VOD) options, or doing shopping or banking. Service providers, such as TiVo and ReplayTV, may also sell PVRs. There are a number of PVRs on the market, including TiVo's DVR, SONICblue's ReplayTV, Sony's SVR-2000, and Philips' PTR. There are also products that offer similar functionality but are software-based (such as SnapStream Personal Video Station) or network-based. The Digital Video Broadcasting (DVB) Project is an industry consortium dedicated to the development of standards for PVRs and other digital video technologies.
There are a number of controversial issues surrounding the capabilities that PVRs and similar technologies enable. For example, ReplayTV makes it possible to skip through commercials by using a 30-second "auto-skip" function. This capacity is popular with consumers, but not with advertisers. Another feature, the ability to download programming from the Internet and to send files to friends, is similarly unpopular with service providers, since it can enable a user who hasn't paid for a service (such as HBO) free access.