I’m still amazed how useful DOS can be, even in 2010! And the main reason I thin it’s the most revolutionary OS of all times is that it actually brought the entire PC industry to regular folks’ hands.
Now, by DOS, I’m actually referring to the simplest form of OS environment, IO.sys, MSDOS.sys and COMMAND.com. That’s all you need in order to communicate with your system. That’s all you need to actually get some work done! Isn’t it amazing?
Obviously, Windows and MacOS heavily extended the OS functionality and brought something else in the game. But that’s just evolution. However, DOS on the other hand was truly revolutionary. I may be skipping some other important OS attempts, but DOS was the first OS I ever used as a little kid. I remember when I was about 8 or 9 years old, my grandpa had a, at the time, high-end 286 computer, 512KB of RAM, some 30MB HDD, it was a beast! and it was running DOS. I learnt a few basic commands, such as CD, MD, CLS, COPY etc… just to be able to run Prince of Persia or Wolf3D