††††CCTV stands for closed-circuit television. It is a very local television system in which programmes are sent over relatively short distances. To enable this to happen, the cameras, receiver and controls are linked by cable.
Closed circuit television is used in department stores, banks, large offices, car parks and even shopping centres where it is necessary, for security reasons, to keep watch over people's movements. CCTV can also be used to monitor dangerous industrial processes and allow medical students to observe surgical operations.
Until recently the use of CCTV was restricted by the fact that a considerable amount of light was needed for the camera to produce a picture. However, by using image intensifiers it is now possible for pictures to be obtained at night.
