A Digital Video Recorder (DVR) is a consumer electronic device that records video footage in a digital format onto a hard drive or mass storage device. This system can record from up to 16 surveillance cameras, at once, onto a hard disk. DVR technology is the basis of video surveillance systems. In order to save disk space, the frame rate can be changed from real time to lapse time and because the recorder is digital, the video can be easily transferred over a computer network.