Chakra

Physical Energy (身体エネルギー, Shintai Enerugī?) is a vital force generated within the cells of living organisms. Combined with Psychic Energy (精神エネルギー, Seishin Enerugī?), or force of will and mental fortitude, it can be harnessed to a variety of uses, such as the production of the superhuman stamina used in taijutsu. It can also be used for formation of the energy known as chakra (チャクラ, chakura?), essential to the use of even the most basic of jutsu.[3]

Once created, chakra moves about the body to any of its release (Chakra) points, utilizing a network of passages not unlike the circulatory system. By various means -- handseals being the most common -- it can then be manipulated to the end materializing effects otherwise impossible under the laws of nature, such as walking on water. The quality of chakra can be altered with what is called nature manipulation (性質変化, seishitsu henka?).[4] There are six kinds of nature manipulation. Five basic kinds,[4] more commonly known as the elements.[5]

The five basic kinds of nature manipulations are Earth (Doton), Water (Suiton), Fire (Katon), Wind (Fūton), and Lightning(Raiton).[4] Each element is stronger than the next, but weaker than the previous, with Lightning looping back into Earth. For example, a lightning-based attack would be very effective against an earth-based defense, but easily countered by a wind user. Additionally, elemental techniques can be countered by techniques of the same element, provided the technique being countered is of equal or lesser power.[6] Generally, everyone has a natural affinity to one of these elements, and thus can learn jutsu relying on that element with greater ease. However, having an affinity for one element does not mean that one cannot learn how to use other elements. Most Jōnin are able to use two different elements, while Kakashi Hatake has been shown to use at least four (the only one he hasn't shown is wind).

Certain shinobi have the ability to mix two different elements into a new element. Examples are Haku's Ice (Hyōton) jutsu, mixing Water and Wind into Ice, and the First Hokage's and Yamato's Wood (Mokuton) jutsu, mixing Earth and Water into Wood.[8] The host of the four-tailed beast was capable of using Yōton jutsu, a mix of Fire and Earth.

The sixth nature manipulation has yet to be revealed.