Inertial Navigation System (INS) is a type of navigation system that uses sensors to measure the linear and angular acceleration of an object. It works by constantly updating the position and orientation of the object based on these measurements. INS is self-contained and does not rely on external references such as GPS signals or landmarks, making it suitable for use in environments where these references are unavailable or unreliable. INS is commonly used in aircraft, missiles, and spacecraft to provide navigation and guidance information. It is also used in some ground vehicles and marine vessels. One of the main advantages of INS is its high accuracy and stability, as it is not affected by external factors such as atmospheric conditions or interference.