A ritual is a repeated, structured sequence of actions or behaviors that alters the internal or external state of an individual, group, or environment, regardless of conscious understanding, emotional context, or symbolic meaning. Traditionally associated with gestures, words, or revered objects, rituals also occur in non-human species, such as elephant mourning or corvid object-leaving. They may be prescribed by tradition, including religious practices, and are often characterized by formalism, traditionalism, rule-governance, and performance.
Rituals are a feature of all known human societies. They include not only the worship rites and sacraments of organized religions and cults, but also rites of passage, atonement and purification rites, oaths of allegiance, dedication ceremonies, coronations and presidential inaugurations, marriages, funerals and more. Even common actions like hand-shaking and saying "hello" may be termed as rituals.