Ojigi

Ojigi is the Japanese way of greeting, i.e. a simple bow from the waist. It is also common when thanking or apologizing. It is a sign of respect given by the person bowing to the person bowed before. A whole body language[?] involving Ojigi has been developed. For example, if the person you are greeting has a higher social status, you should show honour and respect for them by bowing lower and longer.

Foreigners are not expected to bow, but it is considered impolite not to return a bow or at least nod.