The goal of competitive swimming is to be the fastest over a given distance. There are 17 male events and 17 female events. Swimming is an event at the Summer Olympic Games, where male and female athletes compete in 13 of the recognized events each. Olympic events are held in a 50 meter pool. Competitive swimming's international governing body is FINA (Fédération Internationale de Natation), the International Swimming Federation.

The four competitive strokes are the butterfly, backstroke, breaststroke, and freestyle (front crawl). While "freestyle" and "front crawl" are often used interchangeably, freestyle is the more common name and is used in almost all competitive, club-swimming or international competitions. A swimmer may swim any stroke or combination of strokes in a freestyle race. Swimmers generally choose to swim front crawl in a freestyle event since it is the fastest and easiest stroke. Disqualification will occur if the stroke is not swam correctly, for example if the swimmer does not touch the wall with two hands during breaststroke.

These strokes can be swum individually or together in an individual medley (IM). The IM order is: 1) butterfly, 2) backstroke, 3) breaststroke, and 4) freestyle. There are two types of relays: medley and freestyle. The medley relay order is: 1) backstroke, 2) breaststroke, 3) butterfly, and 4) freestyle. Each of the four swimmers in the relay swims a predetermined distance, dependent on the overall length of the relay. The three relay lengths are 200 meters or yards, 400 meters or yards, and 800 meters or yards (which is only swam freestyle). In a 50 meter pool, each swimmer swims one length for the 200 relay, two lengths for the 400 relay, and four lengths for the 800 relay. In a 25 meter or yard pool, each swimmer swims two lengths for the 200 relay, four lengths for the 400 relay, and eight lengths for the 800 relay.There have also been 100 yard relays that have been done by 8 and under swimmers, but is very rare except in summer recreation leagues. Many full-size competition pools in the United States have a length of 50 meters and a width of 25 yards (the Olympic pool size, allowing both short course (25 m or 25 yd pool) and long course (50 m pool) races to be held.

There are several types of judges: a starter sends the swimmers off the blocks and may also call a false-start if a swimmer leaves the block before the starter sends them; finish judges make sure the swimmers touch the wall with the appropriate number of hands (one hand for freestyle and backstroke, two for breaststroke and butterfly with the swimmer's hands touching the wall at the same time, not one after another) turn judges check that the swimmers' turns are within rules; stroke judges check the swimmers' strokes; time keepers time the swims; and the referee along with the starter and the officials make sure everything is running smoothly. If an official catches a swimmer breaking a rule concerning the stroke he or she is swimming, that swimmer is said to be disqualified (commonly referred to as a "DQ") and the swim is not considered valid.

There are two types of meets. 'A' meets are official meets that allow qualification for a special or bigger meet if the qualifying time is met. Scores are kept to see how each team did at the end of the season. 'B' meets are used as practice meets, where the normal, or prime stroke is swum if not yet qualified. Scores are not kept.

In the USA and the UK, communities may sponsor competitive swimming leagues for children and teenagers, made up of swim teams. These leagues for the most part adhere to recognized swimming rules, swim the standard strokes, but swim shorter lengths as events in swim meets. These leagues are usually active in the warmer months, and are not directly associated with a national or world swim organization. However, swimmers who begin their competitive swimming experience on such a local swim team may go on to join a nationally-governed team.

In Australia such competition is usually conducted under the auspices of a club affiliated with the State Association which in turn is affiliated with Swimming Australia, the FINA accredited body. This provides a direct pathway to top level competition for those capable of taking it while still providing a more relaxed environment for those whose main intent is to have fun swimming competitively.

Masters swimming is a club sport for adults who have a competitive spirit. Swimming at this level differs from competitive club swimming. In swim meets masters are allowed to compete in the 50, 100 and 200 of backstroke, fly and breaststroke and the 50, 100, 200, 500 and 1650 of freestyle. The age groups are organized into 5 year increments (Masters, 1). “Swimming has continually been identified as the best way to exercise. Stress reduction, weight control, cardiovascular fitness, reduced cholesterol, muscle tone and endurance are all positively influenced by exercise. Masters Swimmers swear by it (Masters, 1).” Shoulder injuries are the most common because of the repetitive motion of freestyle, butterfly, and backstroke. Knee injuries often occur for breaststroke because of the over use