The video from security cameras can be saved on a digital video recorder.
Digital video recorder (DVR) surveillance uses video cameras connected to a DVR to record video for later playback. The incoming video can also be watched in real time as it is recorded.
History
DVR surveillance was developed in the mid-1990s as an offshoot of the same technology used in devices such as the TiVo DVR unit used by consumers to digitally record broadcast, cable and satellite TV programs for later viewing.
Benefits
DVR surveillance has become more sophisticated and less expensive, allowing its widespread use in homes and small businesses. A system can record feeds from video cameras mounted indoors or outdoors, and can include feeds from hidden cameras such as concealed "nanny cams." Tiny DVR devices are available that are so small that they can be connected to a button camera and hidden in a jacket pocket.
Features
Advanced DVRs can record hours or even days of high-definition video from multiple camera feeds simultaneously. The recorded video can be copied onto a DVD for archiving. Since DVRs record video to a hard disk, video from any desired date and time can be reviewed instantly without the need for rewinding or fast-forwarding videotape.
Tags: video from, DVRs record, feeds from, record video, video cameras, video recorder