While the terms "PFD" (Personal Flotation Device) and "life jacket" are often used interchangeably, there are some differences between the two. A PFD is a broad term that includes all types of flotation devices, including life jackets, buoyancy aids, and other devices that provide flotation. Life jackets, on the other hand, are a specific type of PFD that are designed to turn an unconscious person face-up in the water and keep their head out of the water. Life jackets are typically more buoyant than other types of PFDs and are required by law in certain situations, such as when boating on federally controlled waters.