What is the Digital Crown on Apple Watch?
The Digital Crown is Apple's answer to the crown found on mechanical watches. Historically, the crown is used to set the date and time on a wristwatch, and to wind the mainspring to keep the watch running.
Apple Watch users can press the Digital Crown to return to the Home screen, much like the home button on iPhone.
The Digital Crown can also be rotated to zoom and scroll, depending on context. This function of the Digital Crown allows the user to zoom and scroll without having to pinch, swipe or otherwise obstruct the Apple Watch display.