Ojigi (お辞儀), the Japanese way of greeting, is an essential part of Japanese culture. It is a sign of respect given by the person bowing to the person bowed before. It is also common when showing gratitude or apologizing. Sometimes Ojigi also can be seen when an employee receives a call from his boss (his boss cannot see him through a phone call though).
There are several ways of bending, the first is a slow nod, at about 5 degrees. This is the kind of greeting when we meet with close friends, peers, people who are younger than us, and those who rank or social position is lower than us. Second, bent greetings (Eshaku /会釈) 15 degrees. This way is a bit more formalt and used as a greeting to the people who we know but are not familiar with. Third is full bowing (Keirei /敬礼), about 30 degrees . This is a very formal way of bowing. Used to show respect to the employer or to the older person.
The next one is Saikeirei (最敬礼), 45 degrees bow. Saikeirei has a very deep meaning. It is a way of showing a very deep sense of guilt when making mistakes. It is also used to give respect to people with very high rank or social status, such as the Emperor of Japan for example. And the last one and the most rarely used is the kneeling bow (Dogeza 土下座). This one has a truly deep meaning, even more than saikeirei. If someone had made a fatal mistake, for example, the mistake he had done resulted in the death of another person, that person usually does the kneeling bow. It was also the for people to show respect the Emperor in ancient times.
In conclusion, the more we respect or the greater our guilt is to someone, the lower the bow. The most common mistake in Ojigi occurs when foreigners “Bow Handshake”. Bowing is a traditional Japanese introduction (and greeting). Shaking hands is a western tradition. There’s no mixing the two.
*Funny Dogeza video