Hai or Osu?

[granmasterchen]

well i can tell you from my 3 years of being in Japan that "hai" means yes, or i undertand

OSU is word that is used to show as a sign of respect like when you bow to the dojo when entering/leaving or greating/leaving your instructor you say "osu" or when you shake someone's hand you would say "osu" it is a term of respect towards one another in the martial arts fields, but more based on the Japanese systems. The bow has made all over asia and we can see it in our dojos today, the handshake has been around since early europe and has grown world wide. Some styles may make you say OSU during class when you are bowed at all times, some only on certain basis and some dont mention it at all. My suggestion for you is to go over to Japan and view it for yourself in a country that created it and still uses it.