A watch crown is a small button that sits on the side of a watch case. It is one of the most important functions of a wristwatch as it allows you to adjust the time displayed on the watch. The crown is used to wind a watchs mainspring, which provides the energy and power to the watchs internal movement. It is also used to configure additional components of a watch face like the world clocks or a lunar calendar. The crown is divided into different types, including ordinary crown, screw-in crown, crown with shoulder guard, and crown with protective bridge. The crown is an essential yet inherently simple part of a watch that is used to set the time, wind the watch, and configure additional features.