What is an IP camera is question and answer of this question is given below in the form definition.
An IP camera is a digital video Camera which can transmit and receive data packet over intranet (LAN) and internet (WAN). Answer of what is an IP camera in another word is that, it is digital cctv camera which can send and receive video signal to NVR (Network Video recorder) over network.
So Each IP camera has its own IP address which require network for video transmission. Similarly like other network device such as printer, computer and laptop IP camera also have Network and it is connected to the network in similar way.