In track and field, the term "spikes" refers to both the shoes and the metal spikes under the shoes. While shoes vary by event, the actual spikes also vary by length and shape. Although the differences are relatively minor, in sports where a tenth of a second, a quarter of an inch or slight deviation in direction can be the difference between first and second, every minor difference matters.
Track and field spikes vary in length between 3/16 of an inch and 1/2 inch, with the most common being 1/4 inch. There are also "blank" spikes, flat metal pieces used to fill in holes. Different surfaces might demand a longer or shorter spike, depending on the handling on that surface. Also, some events might place a maximum length on the spikes that can be used. In these cases, even if a longer spike feels more comfortable on the track, it's necessary to limit use to that length, or risk disqualification.
There are five basic types of spikes available: pyramid, needle, compression, tartan and blanks. Pyramid spikes are good for dirt, grass and muddy surfaces. Needles, or slims, are used on all-weather, rubber or other synthetic tracks. Compression spikes, also called "Christmas-tree spikes," are also used on rubber surfaces as an alternative to any possible stick that can occur from needle spikes. Tartan are especially dull needle spikes, also for use on rubber tracks, but no others. Blanks, also called studs, are for use on indoor tracks and when running on asphalt.
Shoes made specifically for all-out sprints, such as 100-, 200- and 400-meter races, place spikes only on the front of the foot to minimise the weight of the shoe. Sprint shoes have no heel, are flexible in the middle and include a stiff plate at the front to support the metal spikes and absorb the impact of each step. Middle-distance shoes are similar to sprinting shoes but add a small, cushioned heel for better support throughout the race. Meanwhile, shoes made for long-distance events, between 3,000 and 10,000 meters, have a smaller plate for spikes in the front and place cushioning along the entire bottom of the shoe.
Shoes for jumping events are typically divided between those for long jump, triple jump, hurdles and pole vaults and those used for high jumping. All-around jump shoes feature front-side spikes and minimal cushioning at both the front and heel, similar to middle-distance shoes. In many cases, long jumpers and hurdlers opt to use sprint shoes instead of all-around jumping shoes as the heel cushioning is less important for these events. On the other hand, high jump shoes place spikes on both the front and the back to prevent slipping when the foot is planted before a vertical leap.
Events that place greater emphasis on momentum than speed require stability. Javelin throwers use big, heavy boots with both front and rear spikes to provide a good plant before the throw. Shot put and discus shoes include no metal spikes and come in two types, glide and spin, depending on the event and technique used. Glide shoes have extra gripping in the treads while spin shoes are smoother on the bottom to increase rotational speed.