katana

A katana is a traditional Japanese sword known for its curved, single-edged blade, long grip, and distinctive construction. The name is commonly understood to mean “one blade,” and in modern usage it refers to the long sword worn with the edge upward in a belt known as the obi, contrasting with the older tachi, which tended to be worn edge-down.

Most katanas were forged from tamahagane, a steel made in a traditional tatara furnace from iron sand and charcoal. The blade is typically created by repeatedly folding the steel and grinding to shape, producing a layered hada (grain) pattern. A differential heat treatment, usually by applying clay to the blade before quenching, creates a harder edge and a tougher body, yielding a visible hamon (temper line) along the blade. The blade is mounted with a handle (tsuka) wrapped in rayskin and cord (ito), a guard (tsuba), a fitting (habaki), and a scabbard (saya).

Historically, the katana rose to prominence in feudal Japan during the Kamakura period and became the preferred weapon of the samurai, eventually forming the daisho pair with the shorter wakizashi. It played a central role in combat techniques, including quick draw and cutting methods, and evolved through various schools and styles of forging. In modern times, katanas are produced for traditional arts such as iaido and battōdō, as well as for display and collection. Maintenance involves cleaning, oiling the blade, and proper storage to prevent rust.

Katanas remain a symbol of Japanese craftsmanship and martial heritage, reflecting a long tradition of swordmaking, discipline, and artistry.