a/c fan & engine fan connected?

If someone could point me into the right direction it would be very much appreciated. The other day at a red light i noticed that the a/c wasn't cold but as soon as i started driving again it got ice cold. So i checked (per a friends advise) and sure enough the fan under the hood was not running.
Well today sitting at a light i noticed that the temperature was climbing pretty fast. Again, as soon as i started driving the a/c got cold and the temperature went down.
So i checked under the hood and looked more closely this time. Both of the fans against the radiator are not running. Are these two connected or would there be a fuse that runs them both. I would think that chances are pretty slim that two unconnected fans would go out at the same time. I could be competely wrong thought.