Right: increasingly powerful computers allow even people with rudimentary technical expertise to install and use a surveillance camera system using cheap "webcams". Top-of-the-line systems used by councils etc are more expensive, but, with prices steadily falling, CCTV is looked on by many as an answer to the question of crime prevention.
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Background information
(The following information is an edited version of some of the material found in the Wikipedia entry titled 'Closed-circuit television'.
The full text of this entry can be found at http://en.wikipedia.org/wiki/Closed-circuit_television)
Closed-circuit television (CCTV) 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. The term is most often applied to those cameras used for surveillance in areas that may need monitoring such as banks, casinos, airports, military installations, and convenience stores.
CCTV systems may operate continuously or only as required to monitor a particular event. A more advanced form of CCTV, utilizing Digital Video Recorders (DVRs), provides recording for possibly many years, with a variety of quality and performance options and extra features (such as motion-detection and email alerts). More recently, decentralized IP-based CCTV cameras, some equipped with megapixel sensors, support recording directly to network-attached storage devices, or internal flash for completely stand-alone operation.
Surveillance of the public using CCTV is particularly common in many areas around the world including the United Kingdom, where there are reportedly more cameras per person than in any other country in the world. There and elsewhere, its increasing use has triggered a debate about security versus privacy.
There is strong anecdotal evidence that CCTV aids in detection and conviction of offenders; indeed UK police forces routinely seek CCTV recordings after crimes. Moreover CCTV has played a crucial role in tracing the movements of suspects or victims and is widely regarded by antiterrorist officers as a fundamental tool in tracking terrorist suspects.
Large-scale CCTV installations have played a key part of the defences against terrorism since the 1970s. Cameras have also been installed on public transport in the hope of deterring crime, and in mobile police surveillance vans, often with automatic number plate recognition, and a network of APNI-linked cameras is used to manage London's congestion charging zone.
Even so there is political hostility to surveillance and several commentators downplay the evidence of CCTV's effectiveness, especially in the United States. However, most of these assertions are based on poor methodology or imperfect comparisons.
A more open question is whether most CCTV is cost-effective. While low-quality domestic kits are cheap, the professional installation and maintenance of high definition CCTV is expensive. Gill and Spring did a cost-benefit analysis of CCTV in crime prevention that showed little monetary saving with the installation of CCTV as most of the crimes prevented resulted in little monetary loss. It was however noted that benefits of non-monetary value cannot be captured in a traditional cost-benefit analysis and were omitted from their study. To get a full understanding of the costs and benefits of CCTV in crime prevention these factors would have to be included.
A 2008 Report by UK Police Chiefs concluded that only 3% of crimes were solved by CCTV. In London, a Metropolitan Police report showed that in 2008 only one crime was solved per 1000 cameras. In some cases CCTV cameras have become a target of attacks themselves.