A PVR is a consumer electronic device that has the capability to record anything airing on TV and storing it on a physical drive in digital form. The device allows you to play back all recorded programs. It has the ability to rewind, stop, and or fast-forward the recorded program.
Since the user can record and replay live TV immediately with just a small time-lag, what appears to be live TV can be manipulated, but is in actual sense recorded. The capabilities of a PVR include time marking, non-linear editing, and indexing. Most PVR devices come as part of a subscriber service.