Couplers are devices used to connect two or more components in various systems, allowing them to work together effectively. They are commonly found in mechanical, electrical, and plumbing applications. For example, in railway systems, couplers link train cars, enabling them to move as a single unit. In electrical systems, couplers facilitate the connection of wires or cables, ensuring a reliable flow of electricity. They come in various shapes and sizes, tailored to specific needs, such as fiber optic couplers that join optical fibers for data transmission. Overall, couplers play a crucial role in enhancing connectivity and functionality across different fields.