The funeral generally includes a ritual through which the corpse of the deceased is given up. Depending on culture and religion, these can involve either the destruction of the body (for example, by cremation or sky burial) or its preservation (for example, by mummification or interment). Differing beliefs about cleanliness and the relationship between body and soul mean that a funerary practice that is deeply sacred to one culture may be absolutely taboo in another. When a funerary ceremony is performed but the body of the deceased is not available, it is usually called a memorial service.