Universal couplings are mechanical devices that connect two shafts, allowing them to rotate together while accommodating misalignment. They are commonly used in various applications, such as in automobiles, industrial machinery, and pumps, where precise alignment is challenging. These couplings can transmit torque and motion between shafts that are not perfectly aligned, helping to reduce wear and tear on components. By allowing for angular, parallel, and axial misalignment, universal couplings enhance the reliability and efficiency of mechanical systems, making them essential in many engineering fields.