The tanto is a common Japanese single or, occasionally, double edged knife or dagger with a blade length between 15 and 30 cm.
The tanto was designed primarily as a stabbing weapon, but the edge can be used for slashing as well. Tanto first began to appear partway through the Heian period, however these blades lacked any artistic quality and were purely weapons.
In the early Kamakura period the tanto was forged to be more aesthetically pleasing, and the famous Yoshimitsu (the greatest tanto maker in Japanese history) began his forging. With the beginning of the Muromachi period (1336-1573), constant fighting caused the mass production of blades, meaning that with higher demand, lower-quality blades were manufactured. Blades that were custom-forged still were of exceptional quality, but the average blade suffered greatly. As the end of the period neared, the average blade narrowed and the sori became shallow.
Approximately two hundred fifty years of peace (the Shinto Era) accompanied the unification of Japan, in which there was little need for blades. With weapon smiths given this time, both the katana and wakizashi were invented, taking the place of the tanto and tachi as the most-used pair of weapons, and the number of tanto forged was severely decreased. The only tanto produced during this period of peace were copies of others from earlier eras.
During the late Shinto era there were still few tanto being forged during this period, and the ones that were forged reflected the work of the Kamakura, Nambokucho, or Muromachi eras. Suishinshi Masahide was a main contributor towards the forging of tanto during this age.
Many tanto were forged before World War II, due to the restoration of the Emperor to power. Members of the Imperial Court began wearing the set of tachi and tanto once more, and the number of tanto in existence increased dramatically. However, later on, a restriction on sword forging caused the number of tanto being produced to fall very low.
Tanto are generally forged in hira-zukuri, meaning that their sides have no ridge line and are nearly flat, unlike the shinogi-zukuri structure of a katana. Some tanto have particularly thick cross-sections for armor-piercing duty, and are called yoroidoshi.
They were mostly carried by samurai as commoners did not generally carry them. Women sometimes carried a small tano known as a kaiken in their obi primarily for self defense.
It was sometimes worn as the shoto 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.
Tanto with blunt wooden or blunt plastic blades exist and are used to practice martial arts involving the use of a tanto safely. Versions with a blunt metal blade are used in more advanced training or demonstrations.
Is a fighting knife very similar to tanto except for the tsuba (sword guard) which it doesn’t have at all. Its blade is detached from sheath and its handle and has a small elevated band, which forms with edging of mouth of sheath as if two halves are a single whole.
The hamidashi was mainly the property of women of the samurai class, and may have been kept concealed in the sleeve of her kimono.