900-1596)
* Shinto (new swords, 1596-1780)
* Shinshinto (new new swords, 1781-1876)
* Gendaito (modern or contemporary swords, 1876-present)

The predecessor of the Japanese sword has been called . In the middle of the Heian period (794-1185), samurai improved on the warabiteto to develop (early Japanese sword). To be more precise, it is thought that the [[Emishi]] improved the warabiteto and developed with a hole in the hilt and without decorations