I remember that the computer lab at my school in the early 90s was still on TRS-DOS, which had zero market share after the mid-80s. That’s probably why all we could do was play a very primitive version of Oregon Trail.
TRSDOS (which stands for the Tandy Radio Shack Disk Operating System) is the operating system for the Tandy TRS-80 line of eight-bit Zilog Z80 microcomputers that were sold through Radio Shack from 1977 through 1991. Tandy's manuals recommended that it be pronounced triss-doss. TRSDOS should not be confused with Tandy DOS, a version of MS-DOS licensed from Microsoft for Tandy's x86 line of personal computers (PCs).
The Z-80 computer does not have the classic meaning of a desktop computer!
This is bogus, because it only includes the op. systems sold and does not include the free linux and android.