I suggest doing some research online for that, there are way too many items to discuss here. However, I will leave this open as I am sure others will weigh in and I think it is a good subject for discussion.
I will list some sites to help:
Japanese Business Culture, Doing Business in Japan, Japanese business practices and awareness, protocol and Japanese customs, negotiating, business etiquette
Japanese Customs, Etiquette, and Culture -- U.S. Commercial Service Japan
Both of those are more geared to business relationships but they should shed some light on general differences, as another suggestion, remember google is your friend.