A gear mechanism is a system that uses interlocking gears to transmit motion and force. Gears are circular objects with teeth that mesh together, allowing them to turn and transfer energy from one gear to another. This mechanism is commonly found in machines, vehicles, and clocks, where it helps control speed, torque, and direction of movement. The arrangement of gears can vary, with different sizes and numbers of teeth affecting how they interact. For example, a larger gear will turn more slowly than a smaller gear when they are connected, which can be useful in applications like bicycles or automobiles to optimize performance.