A brief history of operating systems
“in the beginning”, the OS was just code to which you linked your program, loaded the whole thing into memory, and ran your program; basically, just a run-time library
simple batch systems were first real operating systems:
- os was stored in part of primary memory
- it loaded a single job (from card reader) into memory
- ran that job (printed its output, etc.)
- loaded the next job...
- control cards in the input file told the os what to do
Spooling and buffering allowed jobs to be read ahead of time onto tape/disk or into memory.