Unlike typical casual socks that are often made of cotton, running socks are constructed with high-performance fabrics that dry quickly and can wick sweat away from your feet, allowing the feet to stay cool, dry, and blister-free. The fabric blend often contains a stretchy material, such as spandex, so that the socks contour to the shape of the foot. The snug fit prevents the sock from slipping and bunching, helping you to avoid chafing, blisters, and overall discomfort.