 John Williams composed the film's score, which earned him an Academy Award and was later ranked the sixth-greatest score by the American Film Institute.The main "shark" theme, a simple alternating pattern of two notes—variously identified as "E and F" or "F and F sharp"—became a classic piece of suspense music, synonymous with approaching danger (see leading-tone).Williams described the theme as "grinding away at you, just as a shark would do, instinctual, relentless, unstoppable."