Oi, that graph. The graph doesn’t show age, it shows longevity. MS-DOS may have been developed for 19 years, but it’s way older than that.
1961 at least with Burroughs MCP on B5000.
Per Brinch Hansen has even more with batch or Atlas likely being first if we’re focusing on practical:
https://lobste.rs/s/kj3wpv/evolution_operating_systems_2000
Oi, that graph. The graph doesn’t show age, it shows longevity. MS-DOS may have been developed for 19 years, but it’s way older than that.
1961 at least with Burroughs MCP on B5000.
Per Brinch Hansen has even more with batch or Atlas likely being first if we’re focusing on practical:
https://lobste.rs/s/kj3wpv/evolution_operating_systems_2000