The Austin said:
No, Katanas were used by Ninjas, the Samurais Mortal Enemy, while Samurais used Samurai Swords. Katanas were just based in the Samurai Sword.
I think.
anime is not history. video games are not history. everything you just said was incorrect.
"The katana (刀?) is Japanese for backsword and often refers to the uchigatana after the Muromachi period, which is a type of Japanese sword (日本刀, nihontō?), also commonly referred to as a "samurai sword.[1]
In the strictest sense, the term katana in Japanese is applied to any kind of single-edged sword, of any origin, and does not necessarily refer to a Japanese sword.
"Katana" was originally used as a general term for a single-edged sword having a "sori" or curvature of the blade. While the "sugata" or form can take many shapes, including double edged, the term is now used incorrectly to describe nihontō that are 2 shaku (606 mm / 24 in) and longer, also known as "dai" or "daito" among Western sword enthusiasts"
(taken from the goddamned wikipedia page, one google search away.
http://en.wikipedia.org/wiki/Katana )
'ninja' swords had straight blades. the word 'katana' implies a curved blade.
ninja and samurai were not mortal enemies.
please read more real books.