A single CCTV surveillance system utilizes multiple security cameras and may contain a mix of different kinds and models. The surveillance cameras can be placed indoors as well as outdoors, yet only waterproof cameras can survive outside. Certified weatherproof cameras are able to successfully combat direct sunlight, flowing water, and saturated air with moisture. All cameras models have different features such as number of TV lines (resolution) which enhance sharpness with higher number of lines, Lux number – lower the number, better the light sensitivity at dusk and dawn. Also, a larger sensor size can capture more light to produce less noise and overall a better picture. IR Night Vision is an ability to see in complete darkness with Infrared illumination provided by built in IR LEDs.