Groping for an explanation of the world around them, the earliest humans developed the first concepts of religion. These early forms of worship attempted to give order to the world and assign humans a role in the universe. Gradually the rites of worship grew more sophisticated with sacrifices, ceremonies, vigils, symbology, sacred items, and prayer. One significant step in the advance of worship was the Ceremonial Burial, often a preparation for an afterlife. The remains of Ceremonial Burials offer some of the most detailed information available of past civilizations.