Sure ... The CCD image chip that is at the heart of any camcorder reacts to light. This includes both the light visible to the human eye as well as light in the infrared spectrum (infrared light has a shorter wavelength than visible light ... our eyes simple aren't "tuned" to react to infrared). When you switch a comcorder over to "night vision", it typically turns on an infrared light source (think ... a flashlight you can't see). The infrared light illuminates the subjects and the camera's image sensor reacts to this reflected light, converting it into a TV signal you can see. Typically, it does not distinguish color, so the resultant recording looks like an old black & white film.
Your remote controls also uses infrared pulses to transmitb it's signals. Try pointing a remote at your night vision camcorder and pushing buttons for proof.
This got very interesting a few years ago when Sony released a "Night-Shot" camcorder that could be turned on in the daylight. Using a special filter on the camera lens, many people claimed the setup had the ability to "see through" loose fitting clothing. There was a short-lived frenzy and it made the evening news for a few days. Sony reacted by changing their camcorder design so you could not turn on "Night-Shot" in bright sunlight. There never was much proof of the theory presented, although there were a few shots posted on the web, who knows if they were faked.
EDIT --> I just searched this on the web and was surprised to learn that the whole issue of "Night-Shot X-Ray Vision" is making a comeback ... check it out in Link Removed or this one from Capture Magazine.
Believe it or not ... I actually bought one of the "x-ray camcorders" just before the story broke. I've never got the necessary filter to test it out, but I suppose I still could.
I think that Sony thing is meant to be true. You can turn my panasonic's '0 Lux' mode on in daylight. It has tiny little IR beams on the front that are turned on but the point is that IR radiation is everywhere so even without these you will see very clearly into areas too dark for the normal output.
It is not thermal imaging so don't expect to feel like Predator!!