A suitably specified and professionally installed surveillance system can be utilised in quite a number of applications, for example:
The technology utilised in providing the above has improved dramatically since the advent of the first CCTV tube-cameras and video-machine-style recording systems.
Cameras now utilise CCD or CMOS technology and are either (as in the case of tube cameras) so-called analogue-signal type, or new generation IP-signal based (digitally-coded analogue-signal transmitted via LAN/WAN/Internet).
The means of video signal transmission has also evolved from relatively short-range direct cable-to-recording device RG59 cable link, to long-range twisted-pair and fibre-optic transceiver transmission methods as well as wireless signal transmission. IP-based signal transmission plays a huge role here as well; as a result live video feed can be transmitted over far greater distances nowadays than previously.
Recording equipment usually incorporates either DVRs (digital video recorders) or NVRs (network video recorders), that allow multiple live display configurations and quick video search; sustained video-footage quality as well as multiple networking capabilities and support for alternate, mobile storage formats (such as USB memory stick).
Including box/dome/bullet/vandal-resistant/covert/thermal/IP cameras, camera housings, lenses, illuminators, wireless transmitters/receivers, twisted-pair converters, fibre optic, DVR/NVR.