Apple was recently granted a registered trademark for the startup sound of the Mac, Patently Apple reports. The original chime sound was created by Apple programmer Jim Reekes, who designed many of the system sounds for the Mac OS. The chime has been used in several different variations over the years, including a shift in pitch to the current tone that Apple has been using since early 1999.
Check out the video below to hear all the startup chimes Apple has ever used on the Mac.