Waders are pants that allow an angler to walk into the water (or wade) to access fish or a fishing spot while staying dry.
Chest waders usually have suspender straps that go over the shoulder to stop them falling down.
Hip waders finish just below the waist and can only be used to access shallow water.
The most versatile and comfortable waders are made from Gore-Tex. It is breathable and lightweight but still waterproof.
Neoprene waders are also good and are used for retaining warmth in really cold environments.