From Academic Kids
A ritual is a formalised, predetermined set of symbolic actions generally performed in a particular environment at a regular, recurring interval. The set of actions that comprise a ritual often include, but are not limited to, such things as recitation, singing, group processions, repetitive dance, manipulation of sacred objects, etc. The general purpose of rituals is to express some fundamental truth or meaning, evoke spiritual, numinous emotional responses from participants, and/or engage a group of people in unified action to strengthen their communal bonds. The word ritual, when used as an adjective, relates to the noun 'rite', as in rite of passage.
Rituals may express a part of a larger social doctrine, or simply of a personal one. In religion, a ritual can comprise the prescribed outward forms of performing worship, the cultus or cult of a particular observation within a religion or religious denomination.
Although ritual is often used in context with worship performed in a church, the actual relationship between any religion's doctrine and its ritual(s) can vary considerably from religion to religion. Ritual often has a close connection with reverence, thus a ritual in many cases expresses reverence for a deity.
Outside worship and reverence, rituals can have a more basic sociological function in expressing, inculcating and reinforcing the shared values and beliefs of a society. Rituals range from the grand and ceremonial (such as royal coronations) to the trite and everyday (such as hand-shaking when people meet).
Among other rituals that are not religious in nature are graduation ceremonies, presidential inauguration ceremonies, and oaths of allegiance. Ritual thus is as much political as ritual in orientation.
Rituals have formed a part of human culture for tens of thousands of years. The earliest known evidence of burial rituals dates from around 20,000 years ago. (Older skeletons show no signs of deliberate 'burial', and as such lack clear evidence of the materialization of ritual.)
In psychology, the term ritual sometimes refers to a specific action or series of actions that a person performs in a given context which otherwise has no apparent reason or purpose. The term may refer especially to compulsive behaviors of people afflicted with obsessive compulsive disorder (OCD).