Ninja Swords

Often depicted as a straight bladed weapon with a square guard, ninja swords are an area of historical controversy.

Historically, straight single-edged blades existed, and these were known as choku-to ("straight swords"). As the Japanese sword originally evolved from the Chinese straight-bladed jian, the Japanese sword was straight prior to the use of clay, which insulated the body and exposed the edge in the final heat treatment and water quenching - the result of which was a naturally formed curve due to metallurgical differences in the harder edge and softer body.

The essence of ninjutsu is deception. A shorter blade is far more quickly drawn than a longer blade, and much of classical samurai swordsmanship predicated distancing based on standard blade lengths. Thus a ninja would have the element of surprise in drawing his sword much quicker and at a closer distance than his opponent with a regular-length blade. This split-second advantage may be the turning point in a conflict.