Operating Systems books

Someone lent me this wonderful book:

• William Stallings, Operating Systems: Internals and Design Principles. Seventh edition, Prentice hall, 2011.
  

It really is a beautiful book on operating systems for people that are interested and don't know much about hardware (or where to begin!).

I might write up some notes on the relevant information on hardware. But it is an excellent book, I'll try expanding on its virtues later.