A custom (also called a tradition) is a common way of doing things. It is something that many people do, and have done for a long time. Usually, the people come from the same country, culture, or religion. Usually, they do not know when the custom started.

Many customs are things that people do that are handed down from the past and the Future. Examples of it are:

• Ceremonies is a class of customary, collective action.
• In some countries bowing to older people is polite and respectful.
• In some countries it is okay to burp while eating food.
• In some countries you take your shoes off before entering the house.
• In some places they sit on the floor and eat.