BY definition, Closed-circuit television referred to as CCTV uses video cameras to transmit a signal to a specific place on a limited set of monitors. The technology differs from broadcast television because the signal is not openly transmitted even though it may use point-to-point wireless links.

Used most frequently for surveillance, CCTV is used in areas that may need monitoring. The examples are endless but most common examples include use at banks, airports, retail shopping centers, correctional facilities, military installations, convenience stores, airports, courtrooms, and factory floors. Although not typically top of mind, CCTV is also commonly used as a tool for distance education, making the virtual classroom more of a reality for teaching.

Frequently found at the shop floor and in industrial plants, CCTV is used to observe the parts of a process or production line from a central control. This is especially helpful when the environment is not suitable for human workers. Examples of this would be processes in a chemical industry, the interior of reactors or facilities for manufacturer of nuclear fuel. Temperatures of processes can also be measured by thermo graphic cameras.

The technology of CCTV can work continuously or only as required to monitor a particular event. An event would trigger or alert the CCTV to activate; the event may very well also trigger a phone call, an email, SMS, or other notification for action to take place. Many cities and motorway networks make use of extensive traffic-monitoring systems. CCTV is used to detect congestion and send alerts about accidents. Web applications, that use this type of data, now sit on your laptop or is streamed to your mobile phone and assist with your travel plans.

Footage which is captured from the CCTV is typically stored for later use. Advancements in miniaturization and speed, allow recordings to be stored for many years utilizing a device called a digital video recorder (DVR) or a personal video recorder (PVR.) These devices record video in a digital format and the data is stored to a hard disk drive, a USB thumb or key drive, memory card or a variety of other memory medium within a device.

First installed by Siemens AG, the first CCTV system was used for observing the launch of long range ballistic missiles developed by the end of World War II. Much later, the use of CCTV became common for use in banks and retail stores to discourage theft by recording potential evidence useful for criminal prosecution.

The increasing public use of CCTV worldwide does result in inflamed debate in many countries about security versus privacy, as more and more CCTV cameras are being installed by governments, shop owners, and private parties. Warning signs are typically posted in or around premises being monitored by cameras. Unfortunately, and maybe because of the abundant use of CCTV, there is little evidence that it deters crime. Rather, CCTV should be considered as one component in a comprehensive physical security program.

Unfortunately, CCTV is not only used for the good of the community. There is extensive and creative criminal use, I guess you can say, the burglar alarms are being used by the burglars. Illegal use of a hidden surveillance camera may capture your personal identification number (PIN) at the ATM, a camera could be placed to capture unsuspecting photos in a locker room, or movements tracked in planning a kidnap. The hideous use of the same technology that protects us can also cause harm.

Modern CCTV cameras are small, even miniature, and use high definition color. They are a far cry from the first CCTV cameras that were crude, conspicuous, and low-definition black and white. Video Content Analysis, referred to as, VCA is technology that enables cameras to focus and resolve minute details, tracking objects semi-automatically. This technology enables the system to recognize that an object is moving and whether or not it is a person or a vehicle; it can even determine the color of the object.

Technology advancements are relentless as devices become smaller and data can be transmitted faster for cheaper dollars. A human CCTV operator may be a thing of the past, or be responsible for observing many more cameras, as computerized monitoring of images is under development.

With the millions of gigabytes of captured video, the issue of retention, storage, and preservation becomes a more important issue and challenge. The quality of digital recordings are also subject to compression ratios, images stored per second, image size and duration of image retention before being overwritten. Beware that different vendors of digital video records use different compression standards and compression ratios.

It seems that this primer on CCTV is just the tip of what's needed to know about assembling a comprehensive security system, one which balances between your protection and respecting privacy.