Ninjutsu (忍術), sometimes used interchangeably with the modern term ninpō (忍法), is the strategy and tactics of unconventional warfare, guerrilla warfare and espionage purportedly practiced by the shinobi (commonly known outside Japan as ninja). Ninjutsu was more an art of tricks than a martial art. Ninjutsu was a separate discipline in some traditional Japanese schools, which integrated study of more conventional martial arts (taijutsu) along with shurikenjutsu, kenjutsu, sojutsu, bōjutsu and others.
While there is a international martial arts organization representing several styles of modern ninjutsu, the historical lineage of these styles is disputed. Some schools claim to be the only legitimate heir of the art, but ninjutsu is not centralized like modernized martial arts such as judo or karate. Togakure-ryū claims to be the oldest recorded form of ninjutsu, and claims to have survived past the 16th century.
Spying in Japan dates as far back as Prince Shōtoku (572–622), although the origins of the ninja date much earlier. According to Shōninki, the first open usage of ninjutsu during a military campaign was in the Genpei War, when Minamoto no Kuro Yoshitsune chose warriors to serve as shinobi during a battle; this manuscript goes on to say that, during the Kenmu era, Kusunoki Masashige used ninjutsu frequently. According to footnotes in this manuscript, the Genpei War lasted from 1180 to 1185, and the Kenmu Restoration occurred between 1333 and 1336. Ninjutsu was developed by groups of people mainly from the Iga Province and Kōka, Shiga of Japan.
In the manga and anime series Naruto, by Masashi Kishimoto, a jutsu (術, lit. "technique" or "skill") refers to the abilities that a ninja can use. The series occurs in a fictional universe in which different countries fight for power using ninja soldiers. The Naruto storyline follows a group of young ninja from the village of Konohagakure (Hidden Leaf Village). In this series, ninja use jutsu by manipulating a form of energy known as chakra, a combination of the physical and mental energies into either of the other two main jutsus.
Series creator Masashi Kishimoto developed the concept of jutsu to explain the supernatural feats ninja perform in the series, and also to provide an original image of ninja in manga. The incorporation of jutsu into the series has received both praise and criticism from several anime and manga publications. T.H.E.M. Anime Reviews asserted that jutsu were the primary focus of Naruto and the source of its "highest accolades," but criticized the overly repetitive use of certain jutsu in fight scenes.Anime News Network agreed with this sentiment, calling the fights "repetitive to a fault," but praised the visual presentation of jutsu in both the anime and manga.