The Japanese sword which is a single-edged sword is considered to have changed from a straight sword to wanto (scimitar), and sword-wielding techniques were also changed and developed after the middle of the Heian period.
刀剣のうち片刃のものである日本刀は平安時代中期以後、直刀から彎刀へ移行し、操刀技法も変化、発達したとみられる。