Case of the watch: the exterior covering that guards the movement and inner workings of the watch against dust, moisture, and impact. Cases come in all shapes, sizes, and materials- from stainless steel to gold or titanium- and frequently are a watch's defining aesthetic beauty feature. Cases will also dictate the amount of water resistance a watch can achieve, with some being built to handle the extreme pressures involved with a dive. So, if you're seeking a watch to bring along on dives, you would want to explore this.
Round, rectangular, square, or an almost impossible shape to describe, cases can make every watch unique compared to the others. As a whole, the case is simultaneously a protective component and a style expression.