Except for our golf, cycling, and hiking socks, all of our performance socks are contoured from left to right. This means that the inside of the sock is thicker than the outside. This design allows for better circulation and reduced risk of injury from stubbing toes or other mishaps. Of course, not all feet are created equal. If you have thick ankles or no ankles at all, then these socks may not be for you. Additionally, not every brand of shoe includes a sock. So if you're shopping online without knowing any better, you might find some brands with only men's socks or only women's socks. But generally, shoes include both male and female pairs of socks. And while there may be one style of shoe that has matching left and right socks, such as athletic shoes, most people have different sizes of feet, so they need two different types of socks.