The basic systems consist of a few cameras that go through a device called a 'quad' processor. This system allows multiple cameras to appear on one screen. That screen can be a dedicated monitor or an unused channel or input on your television. You can add to that by installing a digital video recorder, similar to a TIVO system, that will record what the cameras see for weeks. Most modern systems can be programmed to only record when there is motion, so they can record more and you don' t have to review as much.

Computer Networking
The next step up is to connect that digital video recorder (DVR) to your internet router. Now you can access the system from any computer in your home. Want more power? You can pay for off-line services that will store what your DVR stores, OFF-SITE! So even if your DVR is stolen or destroyed, the information will be store on the internet for you to access or provide to the police

Door and Gate Intercoms
By far the most popular application for home CCTV cameras. Mini cameras can be installed in most of today's intercoms. For better clarity, however, full-sized cameras at or near the intercom are preferred.