Germans are generally very formal in their social interactions, and they rigidly divide their personal and business lives. Germans also tend to want to follow strict cultural and traditional rules.
A German work custom is to never work late, as it is believed that needing to work after hours shows that one did not plan his day accordingly or use his time wisely. Communication and social interaction among Germans is very formal. Public greetings are done with a handshake rather than a hug, even with close friends and family. Formal titles are considered very important, and they must be used when introducing someone. It is also proper etiquette to wait for a host or hostess to introduce a new person to a group rather than having the individual introduce himself.
Interactions are less formal in the privacy of the home, but it is customary to only invite close friends and relatives into one's home. One very important custom is not working or making loud noises on Sunday. No one should be out of the house shopping, washing cars or running errands on Sundays. Citizens are also expected not to make loud noises or host parties on Sunday, according to both custom and German law.