The DVR is a device that records video from analog cameras to one or more hard drives. The term DVR is also used by the consumer TV market. The DVR used in the security market has a fixed number of BNC connections to attach cameras. DVRs are available with 4, 8 16, 32 and 64 channels (or connections). This means that you have a maximum number of cameras that can be supported by one unit. Once you exceed the number of connections available on the DVR, you will need to add another DVR to your system. Some DVRs connect to the network and can be viewed using a Windows computer. These were very popular in the 1990s.
