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 (P2P), 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 (Videotelephony is seldom called "CCTV").
Surveillance of the public using CCTV is common in many areas around the world. Video surveillance has generated significant debate about balancing its use with individuals' right to privacy even when in public.
In industrial plants, CCTV equipment may be used to observe parts of a process from a central control room, especially if the environments observed are dangerous or inaccessible to humans. CCTV systems may operate continuously or only as required to monitor a particular event. A more advanced form of CCTV, using 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 cameras, perhaps equipped with megapixel sensors, support recording directly to network-attached storage devices, or internal flash for completely stand-alone operation.
By one estimate, there will be approximately 1 billion surveillance cameras in use worldwide by 2021.[needs update] About 65% of these cameras are installed in Asia. The growth of CCTV has been slowing in recent years.[unreliable source?] The deployment of this technology has facilitated significant growth in state surveillance, a substantial rise in the methods of advanced social monitoring and control, and a host of crime prevention measures throughout the world.
A security alarm is a system designed to detect intrusions, such as unauthorized entry, into a building or other areas, such as a home or school. Security alarms protect against burglary (theft) or property damage, as well as against intruders. Examples include personal systems, neighborhood security alerts, car alarms, and prison alarms.
Some alarm systems serve a single purpose of burglary protection; combination systems provide fire and intrusion protection. Intrusion-alarm systems are combined with closed-circuit television surveillance (CCTV) systems to record intruders' activities and interface to access control systems for electrically locked doors. There are many types of security systems. Homeowners typically have small, self-contained noisemakers. These devices can also be complicated, multirole systems with computer monitoring and control. It may even include a two-way voice which allows communication between the panel and monitoring station.
Wallingford (/ˈwɒlɪŋfərd/) is a historic market town and civil parish on the River Thames in Oxfordshire, England, 12 miles (19 km) north of Reading, 13 miles (21 km) south of Oxford and 11 miles (18 km) north west of Henley-on-Thames. Although belonging to the historic county of Berkshire, it is within the ceremonial county of Oxfordshire for administrative purposes (since 1974) as a result of the 1972 Local Government Act. The population was 11,600 at the 2011 census.
The town has played an important role in English history starting with the surrender of Stigand to William the Conqueror in 1066, which led to his taking the throne and the creation of Wallingford Castle. The castle and the town enjoyed royal status and flourished for much of the Middle Ages. The Treaty of Wallingford, which ended a civil war known as The Anarchy between King Stephen and Empress Matilda, was signed there. The town then entered a period of decline after the arrival of the Black Death and falling out of favour with the Tudor monarchs before being called on once again during the English Civil War. Wallingford held out as the last remaining Royalist stronghold in Berkshire before surrendering after a 16-week siege. Fearing that Wallingford Castle could be used in a future uprising, Oliver Cromwell ordered its destruction.
Since then Wallingford has become a market town and centre of local commerce. At the centre of the town is a market square with the war memorial and Wallingford Town Hall to the south, the Corn Exchange theatre to the east and numerous shops around the edges. Off the square there are alleyways and streets with more shops and a number of historic inns. Although it was a small town, Wallingford once had 14 churches; now, there are three ancient churches within the Parish of St Mary-le-More and St Leonard, a modern Roman Catholic church, a Quaker Meeting House dating from 1724 and Baptist, Methodist and community churches.