Incense is composed of aromatic biotic materials, which release fragrant smoke when burned. The term "incense" refers to the substance itself, rather than to the odor that it produces. It is used in religious ceremonies, ritual purification, aromatherapy, meditation and for creating a mood. The use of incense may have originated in Ancient Egypt, where the gum resins and oleo gum resins of aromatic trees were imported from the Arabian and Somali coasts to be used in religious ceremonies.