Yes, There Is a Difference Between Shams and Pillowcases

According to the internet, the phrase "sham," at least in the context of bedding, has its origins in trickery. In the 1700s, cases with removable decorative fronts first came into fashion and were appropriately labeled "shams." Since then, people have been using similar ornamental cases on their beds for decoration. Here's where you pragmatic types out there might scratch your heads just a little bit--why have pillows meant only for show? And what's a sham exactly? Isn't it just a pillowcase?