Amiga DOS versions

• OS 1.0:
  The developers' version
• OS 1.1:
  First version for end user, was only used in the first US models (A1000)
• OS 1.2:
  Improved Version of OS 1.1, some bugs were removed. OS for A1000 and A500.
• OS 1.3:
  Improved again. Further bugs were removed. Default OS for A500 and A2000.
• OS 2.0:
  New version with more ways to configure the AMIGA. Some memory addresses (in the ROM) have changed so that some games (which did not conform to Commodore's style-guide for programmers) do not run anymore. Default OS for A500+ and A600.
• OS 2.1:
  Improved version which is able to make the AMIGA work in different languages. Default OS for A3000.
• OS 3.0:
  This version is a further development of OS 2.x. The multi-language-support was going on, but artificial speech (programs "Say", "narrator.device" and "translator.library") must be taken from a former version. It is now possible to use 256 different colors on the Workbench screen.
• OS 3.1:
  Improved version. Has an own file-system for CD-ROM drives. Some bugs have been removed. Default OS for CD32, A1200, 1300, 1400, 1500, 4000, 5000, 6000 and Access.
• OS 3.5:
  Improved version. Some bugs were removed, printer drivers have been improved, the graphical user interface has changed. Published in 04/98.
• OS 3.9:
  the most recent one (2001)
• OS 4.0:
  was planned for end of 1998...