I highly recommend everyone to go through the book http://www.linuxfromscratch.org/ before, or as a complementary direction to, diving into any "operating system" resources mentioned on this page. (you could try this on a QEMU/VMWare/VirtualBox/KVM/whatever instance instead of risking your current hard-drive partition setup).
(alert: it's not really a book, it's a project: to compile and install linux without using any distro! the whole process could take somewhere from 1 day to 1 week, depending on the speed of your machine and your command-line skills.)
Because then you would discover (if you haven't already) that what all these people call "operating system" is essentially only a nucleus of the operating system (kernel) and that there is much more to an operating system than whatever is discussed in an OS class.
Also LFS is enlightening in ways I may not have expressed here. If you successfully go through the process, your first thought might be to roll your own linux distro!
(alert: it's not really a book, it's a project: to compile and install linux without using any distro! the whole process could take somewhere from 1 day to 1 week, depending on the speed of your machine and your command-line skills.)
Because then you would discover (if you haven't already) that what all these people call "operating system" is essentially only a nucleus of the operating system (kernel) and that there is much more to an operating system than whatever is discussed in an OS class.
Also LFS is enlightening in ways I may not have expressed here. If you successfully go through the process, your first thought might be to roll your own linux distro!