Shurikenjutsu

Shurikenjutsu (手裏剣術^?) is a general term describing the traditional Japanese martial arts of throwing shuriken, which are small, hand-held weapons used primarily by the shinobi in feudal Japan, such as metal spikes bō shuriken, circular plates of metal known as hira shuriken, and knives (tantō).^[1]

Shurikenjutsu was usually taught among the sogo-bugei, or comprehensive martial arts systems of Japan, mostly in ninjutsu, as a supplemental art to those more commonly practiced such as kenjutsu, sojutsu, bōjutsu and kumi-uchi (battlefield grappling) or jujutsu, and is much less prevalent today than it was in the feudal era.<sup>[1]

With the abolition of swords during the Meiji period, shurikenjutsu saw a major decline, along with many classical martial arts, and almost died out after the turn of the 20th century as Japan sought to become modernized. In fact, many styles of shurikenjutsu became extinct.  

Shuriken consist of two basic designs:

Bo-shuriken - straight metal spikes, usually 4-sided but sometimes round or octagonal.</sup>  
Hira-shuriken, shaken (or "throwing stars")

^{Two schools specifically devoted to shurikenjutsu exist, Negishi Ryu and Meifu Shinkage-ryū.}