Commonly, the samurai-sword blades are divided into the hira-zukuri type     (without ridgeline) and the shinogi-zukuri type (with ridgeline). There are eight different types of the common samurai-sword blades which are: 

•  Shinogi-zukuri, which is the most common and mostly found in long swords (daito).

  

•  Kanmuri-otoshi.

• Unokubi-zukuri, which is found in short swords (tanto) after the late Kamakura period.

• Shobu-zukuri, which was popular in the Muromachi period and generally, found in short blades.

• Moro-ha, which is found in the tanto from the mid-Muromachi period. Straight blades with two cutting edges are known as ken.

• Kata-kiri-ba, which is found in the short blades and was popular in the late Kamakura and the Momoyama period.

• Kata-shinogi, the blades are generally short.

• Hita-zukuri, which is the most common type for short blades without ridgeline.