A personal flotation evice (also named PFD, lifejacket, life preserver, Mae West, life vest, life saver, cork jacket, life belt) is a device designed to keep a wearer afloat and their head above water, often in swimming pools, rivers, lakes, and oceans. The term includes all types of such devices from life preservers to lifejackets to survival suits. They are available in different sizes and different designs purposed for various levels of protection.