It can be presented with various requirements depending on the task. In some cases, you need high quality recording and good optics - for example, when the camera can not be placed close to the subject of observation, and the recording has to be conducted from afar. Sometimes you need protection from weather conditions and physical impact, but when shooting indoors without it you can get by. There are also controlled cameras (PTZ function, from the words Pan-Tilt-Zoom: rotate, tilt, zoom). And there are situations when all these functions are not needed, and the main task is to simply record what is happening in the room where the observation is being conducted.
A separate class of video cameras is IP-cameras, or network cameras. Their main feature is that this is a standalone network device that you can connect to from any computer on your network to watch video. In this case, the recording can be conducted on a computer, network drive or server with the appropriate software.