A life preserver is a floating device designed to keep someone from drowning by helping them stay above water. The most common type looks like a ring made of buoyant material, often bright orange or red with white stripes, that you can throw to someone struggling in the water. They hang on boat decks and near pools, ready to be grabbed in an emergency.

Life preservers work because they're filled with materials lighter than water, like foam or cork, which naturally float. When someone in trouble grabs onto one, the preserver's buoyancy supports their weight and helps keep their head above the surface. This gives them time to catch their breath and either swim to safety or wait for rescue.

The term can also refer to life jackets, which are worn on the body and keep you afloat automatically. Both types have saved countless lives over the years by giving swimmers and boaters extra time when something goes wrong in the water.

People sometimes use life preserver as a metaphor for anything that rescues you from a difficult situation. A student might call a tutor their life preserver in math class, or someone might describe an unexpected job offer as a life preserver when they needed money urgently.