(Aquatics) Competitive swimming is swimming with the goal to maximize performance, usually the speed of swimming. Competitive swimming became popular in the 19th century, and is an event at the Summer Olympic Games. There are four swimming disciplines regulated by the FINA, swum over different distances.

Freestyle places no restrictions on what action the competitors use, except during the freestyle portion of medley swimming. In practice, almost all freestyle events are swum using front crawl. Events are held at distances of 50m, 100m, 200m, 400m, 800m and 1500m.

Butterfly events require that the swimmer's actions retain bilateral symmetry (the left side of the body has to do the same as the right). Events are held at distances of 50m, 100m, and 200m.

Breaststroke, from which the butterfly stroke evolved, places the additional restriction that the swimmer's hands must be pushed forward together from the breast and that the elbows must remain under the water. It is the slowest stroke, and events are held at distances of 50m, 100m, and 200m.

Backstroke places no symmetry restrictions, but swimmers must lay on their back at all times except during turns to perform the stroke. Backstroke is performed, in essence, as an inversion of the crawl - competitors swing their arms back over their shoulder, alternately, and pull through under the water to provide motive power, with a flutter kick. Events are held at distances of 50m, 100m, and 200m.

In addition to that there are a number of combination events in Competitive swimming.

Relay , where a number of swimmers swim sequentially. Events are held at distances of 4x50m freestyle (short 25 lane only), 4x 100m freestyle and 4x200m freestyle.
Individual Medley , where one swimmer swims Butterfly, Backstroke, Breaststroke, and Freestyle in this order. Events are held at distances of 100m (short 25m lane only), 200m, and 400m.
Medley Relay, where four swimmer swim Backstroke, Breaststroke, Butterfly, and Freestyle in this order. Events are held at distances of 4x50m medley (short 25 lane only) and 4x 100m medley.

At the Olympic Games competitions are held in the following disciplines:

. 100m backstroke Men

. 100m backstroke Women

. 100m breaststroke Men

. 100m breaststroke Women

. 100m butterfly Men

. 100m butterfly Women

. 100m freestyle Men

. 100m freestyle Women

. 1500m freestyle Men

. 200m backstroke Men

. 200m backstroke Women

. 200m breaststroke Men

. 200m breaststroke Women

. 200m butterfly Men

. 200m butterfly Women

. 200m freestyle Men

. 200m freestyle Women

. 200m individual medley Men

. 200m individual medley Women

. 400m freestyle Men

. 400m freestyle Women

. 400m individual medley Men

. 400m individual medley Women

. 4x100m freestyle relay Men

. 4x100m freestyle relay Women

. 4x100m medley relay Men

. 4x100m medley relay Women

. 4x200m freestyle relay Men

. 4x200m freestyle relay Women

. 50m freestyle Men

. 50m freestyle Women

. 800m freestyle Women