 The operating system shipped with the system was IBM's DOS J4.0/V, which was similar to PC DOS.There was often speculation that the TeraDrive was specifically designed as a purpose-made "Software Development Kit", to allow software makers to develop their software titles for the Mega Drive.However, given the release date of the TeraDrive (some years after the initial Mega Drive release), as well as the availability of Sega's own game development hardware, it is unlikely the TeraDrive was designed for this purpose.