A life jacket is a vest designed to keep someone afloat in water, even if they can't swim or are unconscious. Life jackets are filled with foam or inflatable air chambers that provide buoyancy, which means they help push your body up toward the surface instead of letting you sink.

When you wear a life jacket properly fastened, it helps keep your head above water so you can breathe, even in rough waves or if you're tired from swimming. Boaters wear them in case they fall overboard. Kayakers and rafters wear them while navigating rivers. Many pools require young children to wear life jackets until they become strong swimmers.

Life jackets come in different sizes and types. Some are designed for calm lakes, others for ocean conditions. Coast Guard regulations require boats to carry enough life jackets for everyone aboard. Bright orange or yellow colors help rescuers spot people in the water.

You might also hear life jackets called life vests or personal flotation devices (PFDs). Whatever name you use, they serve one crucial purpose: keeping people safe around water by preventing drowning.