What was the first computer operating system you used?

What was the first computer operating system you used?

Computers have been around for some time now, so I'd be interested to know what the first operating system was that you used.

• OS/360

• 2BSD

• Apple DOS

• Atari DOS

• OS-9

• SunOS 1.0

• AmigaOS

• Windows 1.0

• Windows 3.0

• Linux 0.01-0.1

• Windows 2000

• Other

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