Light: The laser only penetrates halfway into the dead, outer layer of your epidermis. It's reserved for mild wrinkles and blemishes. Doesn't require any anesthesia.
Medium: This depth reaches the living epidermis layer of your skin, while vaporizing the dead layer. A numbing cream may be needed when treating sensitive areas.
Deep: The epidermis is vaporized up to the blood vessels. The immediate aftereffect looks like a rugburn, and the skin will clear up within ten days. Numbing creams are usually applied before the procedure, and local anesthesia is used only used for very rare occasions.
Micropeel: The micropeel removes very thin layers of skin, one at a time, spread out over multiple sessions. They're only advised in specific instances, or for exceptionally sensitive skin.