In Japan, people greet each other by bowing. Even amongst family and friends displays of affection are uncommon and bows and verbal greetings are used instead. It is not polite to pat someone on the back, put your hand on their shoulder or hug. Shaking hands is uncommon among the Japanese but exceptions are made for foreigners. It is best to wait and see if a hand is offered first.
Bowing has many functions. It expresses respect, acknowledges someone’s presence, is part of an introduction, is used in apologies, helps to express thanks, is used when making a request or to ask someone a favour. You can bow when saying excuse me, goodnight, goodbye, etc. Bowing is also part of many cultural activities such as tea ceremony and martial arts. Japanese people are so used to bowing that you often see them bowing on the telephone as well.
If someone bows to you the general rule is to return the bow. If you are a foreigner you probably won’t be expected to know bowing etiquette and a nod of the head (forwards) is usually sufficient to acknowledge someone’s bow. You don’t need to return the bow of people in shops though.
Bowing is done by bending at the waist with a straight back, feet together and eyes cast down. Men have their hands at their sides with palms touching the legs and women have their hands in front, on their thighs, and slightly crossed. Bowing is meant to express humility, so the type of bow depends upon the social status and age of the person you bow to. A bow ranges from a small nod of the head to a long, 90 degree bend at the waist. If the greeting takes place on tatami mats, people may get on their knees in order to bow. When bowing to someone of higher social status, a deeper, longer bow indicates respect. The lower the bow, the more you should look down. Most of the time bows are very casual and may only be a nod of the head.
Sometimes bows may be multiple, starting off deeper and gradually getting smaller and shorter as one person does not want to get “outbowed” by the other person they are trying to show respect to.
The Greeting Bow 会釈 eshaku is just a small nod of the head and varies from a 5 degree nod of the head (casual and for friends) to about 15 degrees for people you know or people of similar status, or for acknowledging the bow of another person who is lower in status. It is very common in daily life.
The Respect Bow 敬礼 keirei is around 30 degrees. It is common and is used in more formal introductions, to greet customers or to thank someone. It is often seen in business situations.
The Highest Respect Bow 最敬礼 saikeirei is a 45 degree bow and is for bowing to people of a very high status or to signify deep gratitude, a formal apology or when asking a serious favour.
The Kneeling Bow (touching your head to the floor) is not used much these days and would only be seen in very formal situations or in more extreme situations.