Stopping a moment in time is at the heart of sports photography. When the action in front of a camera is fast, a photograph does more than just preserve a remembered scene; it reveals an image that the eye alone cannot appreciate. One of the earliest and clearest examples of this was the famous sequence of a galloping horse photographed in 1878 by Eadweard Muybridge. Muybridge was employed to photograph the galloping horse to settle a bet made by his sponsor, that would determine whether all four of the horse's legs were off the ground at the same time. They were, but it took a photograph to prove it.
From this basic ability of a camera to freeze a moment in time springs a range of skills for dealing with fast action. In some ways this could be considered more of a technique than an application, but there are certain areas, notably sports, which rely on the treatment of motion and are, at the same time, coherent fields of photography. Fast action has special characteristics, and to capture it well requires fast reactions, a knowledge of the ways in which camera and film respond to movement, and an appreciation of the structure and tensions of the action itself.
