Since the early days of sport, athletes have used athletic shoes to not only heighten performance but protect their feet. As sports have progressed, so have the features of athletic shoes.
The purpose of the athletic shoe is to protect the feet while helping aid sport performance. The four components of an athletic shoe are the outsole, midsole, upper and the insert. The midsole provides cushioning while the outsole gives an athlete traction and protection in the heal and toes. The insert provides support and stabilization for the arch, while the upper holds the foot securely.
Although there are many brands of cheaper athletic shoes, they just don't have the durability, lifetime or protective elements of name brand shoes. You may save money upfront, but will spend more in the long run having to replace your shoes. If cost is a concern, consider buying older models of name brand shoes.
Athletic shoes are made sport-specific to provide added features that are relevant to the sport played. Some examples of this are extra cushioning for running shoes, and extra traction for tennis shoes, adding to the importance of having wearing athletic shoes when involved in sports.