Hello again everyone, we're continuing our series on the magic systems in various manga with Naruto (Fairy Tail, Mx0. While not exactly magic the jutsu of Naruto are very similar especially later on in the series. As always, SPOILERS AHEAD.
The fundamental basis of jutsu of naruto and all of it's other magic like abilities is chakra. Very early on it is explained that chakra comes in physical and spiritual flavors which are mixed and molded by the user to produce an effect. Chakra travels throughout the body through a series of vessels similar to the circulatory system with the junctions referred to as chakra points and a series of 8 major junctions called gates which can be forced open to increase the rate of flow through them. The opening of these gates are also linked to physiological effects such as the removal of the bodies limiter on the muscles, turning the skin red, and the emitting of blue and red steam in addition to increasing strain on the body with the 8th gate guaranteeing death once opened. There is also a structure located around the navel which seems to be a dense collection of chakra vessels and appears as a blue fire when it is shown but it's function is never explained.
Once the chakra has been directed to the desired part of the body it is further manipulated by the ninja either by mental control or aided by the use of hand signs. There are 12 hand signs each associated with an animal of the chinese zodiac but there are additional handsigns beyond these, most notably the distinctive handsign used for the shadow clone jutsu. Some of these handsigns are associated with certain classes of techniques but their exact function is not fully explained. Most likely they serve as a focus with each being associated with a particular manipulation of chakra which with training could be reflexively linked to the handsign. In general handsigns are optional for most techniques since the requisite chakra manipulation is possible without them. However more complex techniques, particularly sealing techniques may require an extensive number of seals which implies a more complex chakra manipulation making it harder to perform them without handsigns.
The next level of chakra manipulation is the optional addition of an elemental nature. There are 5 major chakra elements: fire. water, earth, lightning, and wind. Each element is strong against 1 element and weak to another as shown in the diagram(the arrow points towards the loosing element). Obviously adding elemental chakra to a technique allows a ninja to produce an effect using that element ex. jutsu using fire chakra produce fire. Each element is also stated to have secondary properties such as wind providing sharpness but they rarely come into play outside of the rasenshuriken technique's unique ability to cause cellular damage due to its wind nature. Each ninja has an affinity for a certain element but it is unclear as to if this affinity simply makes techniques of that type easier or if the affinity is necessary to be able to use an element.
Beyond the 5 basic elements several combination elements are used such as ice(made from wind and water) and wood(from earth and water) but these abilities are genetic and referred to as kekkei genkai(bloodline limit) when 2 elements can be combined and Kekei tota when 3 elements are combined(the only example being dust style which utilizes earth, wind and fire). These styles are powerful and some have secondary abilities such as wood style which is able to restrain the tailed beasts.
Well that's all for this week, I hope you enjoyed this overview of chakra.