
A composite video signal (also called baseband video) is a single analog video picture without sound. Think of the yellow "video out" jack on a camera. The frequency spectrum used is roughly 0 to 6 MHz
RF audio/video is where multiple TV channels are on one coaxial cable. The cable going from and antenna to a TV is carrying RF (Radio Frequency) audio/video. This is true if the signals are analog TV, digital TV or even a mix of the two. Current broadcast TV uses frequencies between 54 MHz and 806 Mhz. The advent of broadcast digital TV has actually lowered the 806 MHz high end as some of that spectrum is repurposed to other activities by the FCC.
The cable that brings cable TV into your home is RF audio/video. Again, it can carry analog, digital, or a mix of signals. Cable companies generally use frequencies between 54 MHz and 1 GHz. Although some are looking at the new standards and putting in 3 GHz rated splitters.
The cable that goes from a satellite dish to a receiver, while still technically and RF cable, is often called something different, like satellite feed cable, since the frequencies it carries are wider in range than traditional RF signals. These frequencies range up to 2.3 GHz.