An inflatable lifesaver is a type of RAFT that is designed to be used as a safety device in water. It is typically made of a durable material such as rubber or plastic and is filled with air, making it buoyant and able to float on the surface of the water. The term 'RAFT' is used to describe this type of lifesaving device because it is designed to provide a stable platform for people to stand on while they are in the water.