1) Throwing weapon 
A shuriken (Japanese 手裏剣; literally: `sword hidden in user`s hand`) is a traditional Japanese concealed weapon that was generally used for throwing, and sometimes stabbing or slashing. They are sharpened hand-held blades made from a variety of everyday items, such as needles, nails and knives, as well as coins, washers, and other flat pla......
Small throwing knife.
The Shuriken is the trade mark ninja weapon made famous by the movies and stories about the ninja. The Shuriken was simply a flat piece of metal with sharpened points that were thrown at the enemy.