This year marks the centennial of the known invention of the swimming pool cleaner. These devices owe their evolution to imaginative tinkerers, engineers and designers from all over the world. Like swimming pools, there is almost certainly no single inventor or single swimming pool cleaner that has been recorded in history as the first such machine. However, by tracing key patent records, one can begin to appreciate how these devices, whether suction-side, pressure-side or robotic, developed into the popular swimming pool maintenance products they are today.