I didn't know that; having RT-11 at work and running CP/M at home, there was a 'sort of' similiarity there but not like the same kind of underlying structure be

I didn't know that; having RT-11 at work and running CP/M at home, there was a 'sort of' similiarity there but not like the same kind of underlying structure between CP/M and DOS (hence the reason I was asking). Thanks!