Tanto

From Karate, Kungfu, Wrestling, Mixed Fighting Information Source

A tantō (短刀) is a common Japanese knife or dagger with a usually single or sometimes double sided blade length of about 15–30 cm (6"–12"). There is a disputed saying about the tantō, wakizashi, and katana stating that they are "the same sword in different lengths." The tantō differs from the others as it was designed primarily as a stabbing instrument, but the edge can be used to slash as well. Tantō first began to appear in the Heian period, however these blades lacked artistic qualities and were purely weapons. In the Early Kamakura period high quality tantō with artistic qualities began to appear, and the famous Yoshimitsu (the greatest tantō maker in Japanese history) begins his forging. Tantō production increased greatly around the Muromachi period and then dropped off in the Shinto period ("New sword" period). Shinto period tantō are quite rare. Tantō gained popularity again in the Shin-Shinto Period (New-new sword" period) and production increased, however many Shin-Shinto tantō are of poor quality.

Tantō are forged generally in hira-zukuri, meaning that they have no ridge-line, unlike the shinogi-zukuri shape of a katana. Some tantō are very thick with a triangular type construction and no ridgeline are called yoroidoshi and are designed for armor-piercing.

Tantō were mostly carried by samurai; commoners did not generally carry them. Women sometimes carried a small tantō called a kaiken in their obi for self defence.

It was sometimes worn as the shōto in place of a wakizashi in a daisho, especially on the battlefield. Before the 16th century it was common for a samurai to carry a tachi and a tanto as opposed to a katana and a wakizashi.

Myths about the ninja say that it was a favorite weapon of theirs because of its light weight, and was favored for assassination. It was also a popular weapon among the yakuza.

Tantō with a blunt wooden or blunt plastic blade exist and are used to practice safely. Also, versions with a blunt metal blade exist and are used in more advanced training or demonstrations. Martial arts practicing techniques with tantō include Aikido, Jujutsu, Judo, Karate, Arnis (taking place of dagger)