If there's one shoe style that rules every summer, it's got to be mules. Whether they're adorning the feet of editors at fashion week, being slipped on for a city wedding or providing the perfect "smart flats" for the working woman, this is the style that keeps on giving. It might seem like the shoes have only shot to sartorial fame over the last few years, however, the reality is a little more historic. So what are mules and how did they come into being? And what are the best ways to wear them? Read on to find out more.