A holiday is a day or series of days off work for cultural or religious reasons, usually as an annual tradition. Many holidays also involve customary or traditional activities, such as feasting or the sacrifice of animals. Holidays may also commemorate or celebrate important historical events. On holidays people do not work and or go to school. Every country has holidays on which most people do not work, but individuals themselves may often choose to take days off in agreement with their employer. Holidays are often dedicated to recreational pursuits and therefore most people have a holiday during the summer when the weather is best for outdoor pursuits.

The term is derived from "holy days," reflecting the religious importance many of these days have. In developed western countries many holidays represent important Christian days, such as Christmas, Easter, Good Friday and Sunday. Similar religious holidays are celebrated or remembered in most cultures. Holidays of religious importance may involve a break from work, but many people may also refrain from undertaking certain recreational pursuits to show respect for the importance of the day.