It depends on to whom are you speaking but there are lots of ways. ありがとう - arigatou どうも - doumo どうもありがとう - doumo arigatou ありがとうございます - arigatou gozaimasu/mashita どうもありがとうございます - doumo arigatou gozaimasu/mashita They can end in "masu" or "mashita" depending on the situation. And they vary in politeness.

arigatu guzaimasu its mean thank u and domou arigatu means ty verymuch