Naruto Hand Signs, also called Hand Seals, are used by ninjas to manipulate their chakra, the inner energy that is used to create ninja techniques(Jutsu). Each ninja technique requires one or more Hand Signs to be performed in a certain order.
Naruto Hand Signs were inspired by the Hand Seals of Bhuddism and Hinduism, which are used for meditation and religious purposes, and (unfortunately) are not able to call forth fireballs or control water.
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The twelve general Naruto Hand Signs used by most all ninjas.
There are twelve basic Naruto Hand Signs that all ninja can perform, each of which is named after one of the twelve animals in the Chinese Zodiac. Most ninja techniques require a series of these Hand Signs to be performed, but a skilled ninja can reduce the amount of Hand Signs needed. For example, the powerful Water Dragon Jutsu was initially shown to require 44 Hand Signs, but Tobirama Senju, the second Hokage, was able to perform the technique with just one. Some Naruto Hand Signs are also associated with certain elements. For example, many Fire jutsu end with the Tiger sign which represents fire.
Ino preforms her family's Mind Transfer technique using special Naruto Hand Signs.
Naruto, Sakura and Sasuke performing Summoning techniques.
While the twelve basic Hand Signs are universally used, some techniques require different Hand Signs. Summoning techniques usually requires the user to slam their hand against the ground to perform the summoning while clone techniques have the user make a cross with their middle and index fingers on each hand. Some techniques even require a completely unique Hand Sign, such as the Mind Transfer ninjutsu used by Ino Yamanaka and the rest of her family.
Other Naruto Hand Signs are not used for ninjutsu, but as a signal from ninja to ninja indicating comraderie.
Haku performs seals with one hand
Whether general or special, very skilled ninja can even perform Naruto Hand Signs with only one hand to leave the other open for combat. Others master a certain ninjutsu or overall ninjutsu to a point where they don't even need to use Naruto Hand Signs anymore. The hands used to complete a seal do not necessarily need to be your own. Ninjas can work together, to create a Hand Sign if one is otherwise unable, or can also be forced into collaborating. This means that some Naruto Hand Signs also require more than two hands to perform.
Gamabunta releases the Liquid Bullets ninjutsu
Most ninjas are skilled in the use of ninjutsu, which molds chakra into certain shapes and under specific elemental properties for use in battle. This sounds complicated, but ninjutsu can be as simple as shooting a fireball at your opponent. The second most common type of technique is genjutsu, used to make opponents see illusions. While other types of techniques do exist, such as kenjutsu (sword techniques) and shurikenjutsu (thrown weapon techniques), they appear much less frequently. These techniques are not limited to humans either; summoned animals and Tailed Beasts also have the ability to use Naruto Hand Signs.
Without Naruto Hand Signs, chakra is next to useless for a ninja. Ninjas serve as security for their villages and the counties they live in, operating as a sort of laid-back mix between military and police. Without their special powers, the world of Naruto would certainly be a very different, if not non-existent, place.
