The "Sound Barrier" refers to the point at which an object moves from subsonic speeds (below the speed of sound) to supersonic speeds (above the speed of sound). This transition occurs at approximately 343 meters per second (1,125 feet per second) at sea level, depending on factors like temperature and altitude. When an object approaches this speed, it experiences increased air resistance and pressure waves, which can create a loud noise known as a sonic boom. Breaking the sound barrier was first achieved by Chuck Yeager in 1947, flying the Bell X-1 aircraft. This milestone demonstrated that it was possible to exceed the speed of sound, leading to advancements in aviation and aerospace technology. Today, supersonic flight is used in military jets and experimental aircraft, while commercial supersonic travel is being explored again.