A hollow or skeleton design showcases the intricate internal components of the watch movement. This design creates a visual spectacle and allows you to see the gears, escapement, and balance wheel in action. It's a popular choice for those who appreciate the artistry of watchmaking. Multifunctional watches offer various additional features beyond just telling time. Common multifunction features include chronograph (stopwatch), day/date display, moon phase, world time, and more. The exact functions depend on the watch model. A watch with a skeleton design is often powered by an automatic or mechanical movement to enhance the visual appeal. The multifunction features can be added to these movements for increased functionality.