Sprint Spikes
These shoes are made for 100 meter to 400 meter sprints. These are the lightest shoes on the market. They generally do not have any padding in the heel, and the spike plate under the toes is pretty stiff to force the runner to run on his or her toes.
Hurdling
These shoes are for 100 meter hurdles, 110 meter high hurdles and 400 meter hurdles. Most hurdlers use a more-flexible sprint spike or a middle-distance spike for a small cushioned heel.
Middle Distance
These shoes are recommended for 800 meter to one mile. They're similar to sprint shoes, except they have cushioning in the heel. They're used for slower speeds, so the sole is less rigid so less demanding on the runner's stance. The majority of the running is done on the forefoot, so the spike place is still stiff to encourage this kind of running.
Distance
These are for distances of 3000 meters to 10,000 meters. These shoes have fewer spikes and more cushioning. The soles are flatter, allowing a full range of motion in the foot. These are a bit heavier than sprint and middle-distance shoes, but they are still significantly lighter than regular trainers. These shoes are also used by steeple chasers.
Multi-Purpose
These shoes are just low-end middle-distance spikes that have full midsoles and a generic, flexible spike plate. They're good for every day practice and can be used in running-based events.