Cogs are small, toothed wheels that work together in machines to transfer motion and force. They are essential components in various mechanical systems, such as clocks, engines, and gearboxes. When one cog turns, it causes adjacent cogs to turn as well, allowing for the efficient transmission of energy. Cogs come in different sizes and shapes, depending on their specific function in a machine. They are often made from materials like metal or plastic to ensure durability and effectiveness. The arrangement and interaction of cogs are crucial for the proper functioning of devices, making them fundamental in engineering and design.