Closed-circuit television (CCTV), also known as video surveillance, is the use of video cameras to transmit a
signal to a specific place, the term is most often applied to those used for surveillance
in areas that may need monitoring such as banks, casinos, airports, military installations, and convenience stores
An Internet protocol camera, or IP camera, is a type of digital video camera commonly employed for surveillance, and which, unlike analog closed circuit television (CCTV) cameras, can send and receive data via a computer network and the Internet. Although most cameras that do this are webcams, the term "IP camera" or "netcam" is usually applied only to those used for surveillance.
There are two kinds of IP cameras:
Centralized IP cameras, which require a central Network Video Recorder(NVR) to handle the recording, video and alarm management.
Decentralized IP cameras, which do not require a central Network Video Recorder (NVR), as the cameras have recording function built-in and can thus record directly to any standard storage media, such as SD cards, NAS (network attached storage) or a PC/Server.