Mechanical couplings are devices used to connect two shafts together in machinery, allowing them to transmit power and motion. They help ensure that the shafts rotate in sync, which is essential for the proper functioning of various mechanical systems. Couplings can accommodate misalignment, absorb shock, and reduce vibration, making them crucial in many applications. There are several types of mechanical couplings, including rigid, flexible, and universal couplings. Each type serves a specific purpose and is chosen based on the requirements of the machinery involved. Common materials used for couplings include metal and plastic, depending on the application and load conditions.