What are the different strokes in swimming and how do they differ from each other?

There are four main strokes in swimming: freestyle, backstroke, breaststroke, and butterfly. Each stroke has its own technique and style. Freestyle involves a flutter kick and alternating arm strokes. Backstroke is swum on the back with an alternating arm and flutter kick. Breaststroke involves a frog-like kick and a simultaneous arm pull. Butterfly requires a dolphin kick and a simultaneous arm pull. Each stroke has specific rules and techniques that make them distinct from one another.