Theres a couple of different kinds. The one most people think of is SD - Super Deformed - style; made famous by a parody version of Mobile SUIT Gundam. This features huge heads supported by very squashed bodies. The other, slightly less common style is "Chibi" - Child Body. This features a relatively large head in comparison to the body, but the body is not so squashed as with SD, and the head is not the dominant feature as in SD.The animation is a good example of "Chibi" style for the most part.
"The power of bakers, the power of artists; even the power of witches! It must be a power given by God... sometimes we suffer for it."- Ursula, Kikis Delivery Service.