Chakra
Chakra (チャクラ, chakura?) is the basic energy source necessary for ninja in Naruto to perform most jutsu. Ninja produce chakra through the combination of their two energies: the physical energy (身体エネルギー, shintai enerugī?), drawn from the trillions of cells that make up the human body, and the mental energy (精神エネルギー, seishin enerugī?), gained through experience and meditation. Once created, chakra moves throughout the body in a manner similar to the circulatory system and is delivered to one of 361 chakra release points. By performing a sequence composed of any of twelve different hand seals, chakra can then be manipulated to create supernatural effects, such as walking on water.
During Part II of the series the concept of nature manipulation (性質変化, seishitsu henka?), altering the quality of chakra, is introduced. Nature manipulation allows ninja, following certain training, to convert their chakra into one of five elements: earth, water, fire, wind, and lightning. Each element is stronger and weaker than another element; for example, fire is weak against water, but can easily counter and even gets stronger when used against a wind-based jutsu. Most ninja have a natural affinity for one of the five elements, allowing them to use jutsu of that type with greater ease. Ninja with an affinity for fire, for instance, will be able to breathe fire much sooner than they will be able to manipulate water.
Skilled ninja can learn how to use other elements; ninja of the Jonin rank typically are able to manipulate at least two elements. Kakashi Hatake has been shown using three different elements in the Naruto manga and a fourth in the anime adaptation. Although these ninja can use their different elements separately with little effort, combining the two elements is impossible for ninja who do not have a genetic predisposition for it. Ninja with one of these genetic abilities can mix two specific elements to create an entirely new one. Haku, an antagonist introduced at the start of the series, can mix water and wind to create ice. Mokuton, a combination of earth and water unique to the First Hokage, Danzo and Yamato, allows the user to produce wood.
Read more about this topic: Jutsus