Some feel it should be a broad spectrum light and ideally, I suppose that would be best. Basically though, any light will work. My gang get curly fluorescent in addition to natural daylight. Being that they room windows face west, during fall, winter and early spring, there isn't enough natural light during the day.
The normal "white" curly fluorescent bulbs are very good for UVA. I also use a reptile UVB bulb just to be safe. There is some evidence that desert animals need UVB. I don't know if this is just reptiles or mammals as well.