Gear drives are mechanical systems that use gears to transmit power and motion between different parts of a machine. They are commonly found in various applications, such as automobiles, industrial machinery, and robotics. By changing the size and arrangement of the gears, gear drives can increase torque or speed, making them versatile for different tasks. These systems can be classified into several types, including spur gears, bevel gears, and worm gears. Each type has its unique advantages, such as efficiency and compactness, allowing engineers to choose the best option for specific applications. Gear drives are essential for reliable and efficient machine operation.