Stability Margin is a measure used in control systems to assess how close a system is to becoming unstable. It indicates the amount of change in system parameters, such as gain or phase, that can occur before the system loses stability. A higher stability margin means the system can tolerate more variations without becoming unstable. In practical terms, engineers often use Stability Margin to design systems that can withstand disturbances or changes in conditions. This concept is crucial in fields like aerospace engineering and automotive design, where maintaining stability is essential for safety and performance.