Carnival is traditionally celebrated before Lent in Catholic and Orthodox societies, usually in February. It involves public celebrations and parades with elements of circus performances and masks. The document discusses how carnival is celebrated in different parts of the world, such as the famous Brazilian Carnival and carnivals in India, the Americas, and many European countries. Specifically, it notes that carnival is celebrated for three days in Goa, India, and people of all faiths participate in the festivities.