[fortran77]

> These features made possible Windows 3.0, OS/2, and early Linux.

And also--before Linux--SCO Xenix and then SCO Unix. It was finally possible to run a real Unix on a desktop or home PC. A real game changer. I paid big $$$ (for me at the time) to get SCO Xenix for my 386 so I could have my own Unix system.

[whobre]

Xenix 2.1 could run on the IBM PC XT with Intel 8088 in late 1983, IIRC, and even before that on the Altos 586 which had MMU as an external chip.

[spijdar]

For that matter, the "second" version of UNIX ran on a PDP-11/20 with no memory protection or MMU, and there were a few versions after intended to run on similar hardware (LSX, MINI-UNIX).

The PDP-11's MMU option was closer to the 8088's segmentation model I think, but I've never coded either, so dunno really. It does seem like it was possible to port "PDP-11 UNIX" to a lot more platforms than would get "VMUNIX".

[classichasclass]

Don't forget Venix. It was the first true Unix that could run on a stock IBM PC, and beat Xenix on that platform by months.