[TUHS] advent of "modern" Unix OS

[Paul Winalski via TUHS]

On Sat, Apr 25, 2026 at 12:34 PM Andrew Lynch via TUHS <tuhs at tuhs.org>
wrote:

> I'd propose the modern era began with Unix or variants for 32-bit
> architectures *with* hardware memory protection (MMU) and "large" RAM
> (16MB?).  I'd further say machines of the class became common place
> somewhere in the 1988 to 1990 time frame.


That sounds about right to me.  That is around the time that 16+ MB of RAM
became commonplace.


> I'd say the difference is the advent of full 32-bit architectures with MMU
> like 68020 with its PMMU vs. 68000/68010 or 80386 vs. 80286.
>

Full 32-bit architectures with MMU were commonplace back in the 1960s,
System/360 being a prime example.  They existed long before Unix came
along.  But architectures with a 32-bit word size, memory protection, and
multi-megabyte RAM were not commonplace until the mid-to-late 1980s.

-Paul W.