A festival is an event ordinarily celebrated by a community and centering on some characteristic aspect of that community and its religion or traditions, often marked as a local or national holiday, mela or eid. Next to religion and folklore, a significant origin is agricultural. Food is such a vital resource that many festivals are associated with harvest time. Religious commemoration and thanksgiving for good harvests are blended in events that take place in autumn, such as Halloween in the northern hemisphere and Easter in the southern.