People enjoy swimming for a variety of reasons be they purely recreational or as an excellent cardio-vascular exercise activity.

Swimming can be done in a variety of settings as long as there is water. Swimmers enjoy outdoors swimming in both natural bodies of water and in man-made swimming pools. The average in-ground swimming pool is concrete, lined with a water-proof material and is usually made with a system of filters and pumps to ensure that the water does not get contaminated with algae and other contaminants that can cause bodily harm if ingested. Natural bodies of water swimmers enjoy include oceans, seas, lakes, rivers and swimming pools of fresh water.

A majority of swimming pools and public beaches require patrons to wear a swim suit while swimming. However, there are a number of nude beaches where people can swim and enjoy the beach naked.

There are a great deal of competitive sports that revolve around swimming also. These sports include races in which swimmers compete to see who can go a predetermined distance in the fastest amount of time. These races often require participants to use a specific type of stroke, or way of propelling yourself through the water. Another type of sport that involves swimming is water polo, a sport where participants attempt to throw a ball into the opposing team's goal while treading in deep water.

Humans are not the only animals to swim. In addition to aquatic animals that make their homes in the water, almost all mammals are born with the ability to swim. Even human babies have the instinct to swim and will attempt to dog paddle if placed in a pool.