dvd recorder

This is more of a tv question, but I hope someone here knows. When hooking up a dvd-recorder, there is the tri-colored cable red/yellow/white which also works on the vcr. I hooked that up, and it does not work. I get no indication of anything working with that cable. The other outlet is s-video. Is that used in addition to, or in place of the tri-color? Any help appreciated.