Japanese swords have evolved throughout Japanese history. That fact is entirely lost in popular culture, however, in which Japanese swords, regardless of design, are referred to as "katanas''. In reality, the katana is a fairly recent weapon, relatively speaking, and hadn't been introduced yet during the classical period portrayed in many Jidai movies. Mostly in Japan the common word for sword is ''Katana''. But there are various types of ''katanas''.
Some traditional samurai swords, kept in a museam