According to Home Depot, the best carpet for a high traffic area is a material that features "short and dense loops." Additionally, synthetic fibers such as nylon or polypropylene resist stains and dirt the best.
Carpet is usually made of strands woven together in looped patterns. The density of the looping and the type of material both contribute to the durability of the carpet. The denser the looping, the tighter its weave, and the better it stands up to heavy amounts of foot traffic. Synthetic fabrics are also the least likely to absorb stains while natural fabrics act as sponges.