DVR versus NVR

A DVR is really a multipler with a computer disk for storage. A DVR digitally compresses analog video feeds and stores them on the hard drive. The term digital here refers to the compression and the storage not the video feeds. The DVR has to be located near the analogue feeds.
In contrast a NVR stores digital images directly from the IPnetwork. The feeds have already been converted to digital feeds at the camera so there are no video connectors anywhere on a NVR.