CCTV Surveillance
(Closed Circuit TV) A self-contained surveillance system comprising cameras, recorders and displays for monitoring activities in a store or company. Earlier analog CCTV systems used VHS tape; either a single VCR for each camera, a "quad VCR" that recorded four low-res images or a time-lapse recorder that handled multiple cameras. Subsequently, specialised digital video recorders (DVRs) with multiple analog inputs superseded VHS tape machines. From Analog to Digital Increasingly, digital "network cameras" are used that transmit over Ethernet or Wi-Fi and offer greater camera installation flexibility. Analog CCTV recorders have a fixed number of camera ports, whereas Wi-Fi cameras are easily added, and Ethernet ports can be expanded at minimal cost.
