Mechanical watches use a balance wheel to measure time, and a mainspring for power. You need to wind these watches by hand.

Automatic watches are self-winding mechanical watches. They have a rotor that includes a weight, which swings backwards and forwards with every movement of the wrist and winds the mainspring.

Quartz watches use a quartz crystal for time measurement and a battery for power. You don’t need to wind them.

Kinetic quartz watches are exclusive to Seiko. These are quartz watches without batteries. The kinetic quartz generates electricity from the natural movement of the wearer's arm and wrist, and stores the energy in a capacitor. If left motionless, the reserve energy lasts three to 14 days.

Solar quartz watches use a quartz crystal. Any light is absorbed through the crystal and dial, and a solar cell converts the light into energy to power the watch.