Surveillance is the monitoring of behavior, many activities, or information for the purpose of information gathering, influencing, managing or directing. This can include observation from a distance by means of electronic equipment, such as closed-circuit television (CCTV), or interception of electronically transmitted information like Internet traffic. It can also include simple technical methods, such as human intelligence gathering and postal interception.
Surveillance cameras
Surveillance Camera to support the Washington, DC Police
The headquarters of UK intelligence activities is Government Communications Headquarters, Cheltenham, England (2017)
A surveillance camera in Cairns, Queensland
Closed-circuit television
Closed-circuit television (CCTV), also known as video surveillance, is the use of video cameras to transmit a signal to a specific place, on a limited set of monitors. It differs from broadcast television in that the signal is not openly transmitted, though it may employ point-to-point, point-to-multipoint (P2MP), or mesh wired or wireless links. Even though almost all video cameras fit this definition, the term is most often applied to those used for surveillance in areas that require additional security or ongoing monitoring.
Surveillance cameras on the corner of a building
Surveillance camera in a residential community
Dome camera in Rotterdam central metro station
Desk in one of the regional control-rooms of the National Police in the Netherlands in 2017