I think he is referring to a trail camera hidden away.. I got a cheap one that was on sale from a local retail store.. was affordable and seems to work well.. its got a big ass flash on it though and wouldn't be good for remote security at all.. any trespassers at night would see the flash and take the camera.
now days it sits inside the cat door in a garage window hooked to a power outlet; it gives me a timestamp of there comings and goings incase one turns up missing I can check the last time they went through the door.. lost a couple to Coyotes over the years.