This is a basic informations Video about the Japanese language and its origin.

origin theories:
1.) the Austronesian Hypothesis(Austric)
2.) the Dravidian Hypothesis(Indo-Pacific)
3.) the Creol theory

not mentioned 4.) theory: Altaic.
Altaic was a controversial theory that linked japanese and korean with the central-asian languages(turkic, mongolic and tungusic). This theory is seen as discredited and has no support of modern linguists anymore.