A digital video recorder (DVR, Digital Video Recorder or PVR, Personal Video Recorder) is an interactive device for recording television and video in digital format. It could be considered as a more sophisticated set-top box with recording capacity. A DVR is composed, on the one hand, of the hardware, which consists mainly of a large capacity hard disk, a microprocessor and communication buses; and on the other, the software, which provides various functionalities for the treatment of the received video sequences, access to programming guides and advanced content search.