Shurikens, also known as ninja stars is one of the most common type of weapon you will see in Naruto alongside the Kunai Knives. It is bascially a small metal star with only 4 sharp points and a big hole in the middle, which is there due to being cool and getting rid of excess weight from the shuriken that it doesn't need. The hole though serve other purposes for bigger shurikens. There are many other types of shurikens used in Naruto.
 Giant Shuriken
Another type of shuriken is the Giant Shuriken. It is just like the name implies, it is just the same shape as the small shuriken but bigger. This makes it slower, less devious, but much more devastating. The hole in the shuriken serve as the place to hold the shuriken.
 Fuuma Shuriken
Famous for it's use during the fight against Zabuza, it is the earliest weapon that was introduced in Naruto other than the small shuriken, giant shuriken, and kunai knives. This shuriken, unlike other shuriken, is in layers(one for each blade). There are four blades with the blades shaping more like a sword than just a pointed edge. When it contracts it can be easily stored and it can also be used as metal sword to defend yourself with. The most famous use of this Shuriken is the Shadow Windmill technique which uses two Fuuma Shurikens with one hiding under the shadow of the first.
 Triple Windmill Blade
Famous for its only use in the first fight with Sasuke and Orochimaru, the Triple Windmill Blade is basically like a Fuuma Shuriken except smaller but not as small as the basic shuriken and has only three blades. In his fight against orochimaru, Sasuke is able to control the Windmill using his sharingan, supposively.
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