Hey Blaze, CFLs are Compact Flourescent Lamps, which are the energy saving light bulbs that screw into a regular light socket but are made of either a coiled or u-shaped tube instead of a regular bulb. They are cheap, last long, and you can buy them just about anywhere, like the grocery store, hardware store, or wherever they sell light bulbs. I'm not an expert, but from what I've read you will want to get the highest wattage you can find, also I guess they make cool-white and warm white lamps. The cool ones have more blue light, which helps in the vegetative stage, and the warm ones have more red, which helps with flowering.