A CCTV Camera can be defined as Closed-Circuit Television. The main purpose of a CCTV camera is for surveillance and to detect crimes. It is mainly used in public places such as, museums, banks, schools, offices, etc. Nowadays, you will also find CCTV cameras in people residents as a safety measure.
Hope this provides you more information on CCTV cameras.
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Also read - How to secure your premises by CCTV Camera?