An angel is a supernatural spiritual being in various theistic religious traditions that serves God. Often depicted as benevolent celestial intermediaries between God and humanity in Abrahamic religions and describe angelic hierarchies, which vary by religion and sect. Other roles include protectors and guides for humans, such as guardian angels and servants of God. Those that are expelled from Heaven are called fallen angels, distinct from the heavenly host. Angels are often identified as humans of extraordinary beauty with bird wings, halos, and divine light.