> DOS was hardly an operating system at all Yes, DOS was basically a boot loader and utilities. The EFI shell is modeled the same way, though DOS had fewer ad

> DOS was hardly an operating system at all Yes, DOS was basically a boot loader and utilities. The EFI shell is modeled the same way, though DOS had fewer address bits available. Netware also used it in this fashion, as a boot loader that may/not initialize hardware. From memory, the next stage of the OS would simply write itself over DOS in memory, move the instruction pointer and go.