The International Paralympic Committee recognises the fastest performances in swimming events at the Paralympic Games. Swimming has been part of at every Summer Paralympic Games. Races are held in four swimming strokes: freestyle, backstroke, breaststroke and butterfly over varying distances and in either individual or relay race events. Medley events combine all four strokes, again either as an individual format (swum in order: butterfly, backstroke, breaststroke, freestyle) and as a team relay (swim in order: backstroke, breaststroke, butterfly, freestyle). Competitors are allocated a classification based on their ability in the water, with records available for each event in each classification.