Ceremonial food offerings also are a common practice in Buddhism. The precise rituals and doctrines behind them differ from one school to another. Food may be simply and silently left on an altar, with a small bow, or the offering might be accompanied by elaborate chants and full prostrations. However it is done, as with the alms given to monks, offering food on an altar is an act of connecting with the spiritual world. It is also a means to release selfishness and open the heart to the needs of others.