A swimming pool, swimming bath, wading pool, paddling pool, or simply pool, is a man-made structure designed to hold water to enable swimming and associated activities. Pools can be built into the ground (in-ground pools) or built above ground (as a freestanding construction or as part of a building or other larger structure), and may be found as a feature aboard ships. In-ground pools are most commonly constructed from materials such as concrete, natural stone, metal, plastic, composite or fiberglass, and may follow a standardized size, the largest of which is the Olympic-size swimming pool, or be of a custom shape.
Many health clubs, fitness centers, and private clubs have pools for their members, often used for exercise. In much of the world, local governments provide publicly-run pools. Some of these are outdoors; indoor pools are often part of a leisure centre. Many hotels have a pool for the use of their guests. Pools as a feature in hotels are more common in tourist areas or near convention centers. Many universities and other institutional communities provide pools for their members, often as part of an institution-specific athletic or recreational complex. Apartment complexes and residential subdivisions may provide a pool for the use of their residents. Private residences, particularly in areas with warm climates, may have their own pools.
