DVD-recorder and fan air cooler?

I have borrowed a Philips DVDR80 recorder, and wonder a little about one
thing: when I put a dvd disc into the recorder, it is quite still the
first minutes, but then there are coming more "noise" from the recorder.
So I wonder, are there a fan air cooler inside this recorder, just like
on a CPU in a computer, that makes this noise or is this something
wrong? And is this the same for all such recorders?

John

John