A tanto is a type of Japanese short sword or dagger. It is characterized by its straight, single-edged blade and compact size. The term "tanto" translates to "short sword" or "knife" in Japanese.

Several features define a tanto:

1. Blade Length: Tanto blades typically range from around 15 to 30 centimeters (6 to 12 inches) in length. While they are shorter than the standard katana or wakizashi, tantos can vary in size depending on the specific style and purpose.
2. Blade Shape: The tanto has a straight, single-edged blade, unlike the curved blade of a katana or wakizashi. The blade may feature different profiles, such as a flat or slightly curved edge, or a sharp tip. Some tantos have a slight taper towards the tip, but the overall shape remains straight.
3. Point: Tantos generally have a sharp and durable point, making them suitable for piercing and stabbing. The point can vary in shape, from a sharply pointed tip to a more reinforced and robust design.
4. Construction: Traditional tantos are typically forged using similar techniques and materials as other Japanese swords. They have a blade made of high carbon steel, a hamon (temper line) created during the heat-treating process, and a visible differential hardening line known as the yakiba.
5. Purpose and Use: Historically, tantos served multiple purposes. They were used as self-defense weapons for close-quarters combat, as tools for various everyday tasks, and as symbols of social status or personal adornment. Tantos were also commonly carried by samurai as a backup weapon to their primary swords.
6. Aesthetics and Fittings: Tantos often feature aesthetically pleasing and intricate designs on the blade, fittings, and scabbard. The handle (tsuka) and hilt (kashira) may be wrapped with materials such as silk or rayskin, and adorned with decorative elements like menuki (ornamental grip decorations).

Tantos have a rich history in Japanese culture and are appreciated for their craftsmanship, symbolism, and practicality. They continue to be sought after by collectors, martial arts practitioners, and enthusiasts of Japanese weaponry.