Concepts in operating systems

Friends I like operating systems very much.I have studied every page and corner in the subject.It is a very interesting subject and it must be thoroughly read by the various students studying operating systems.It was a compulsory subject to me during my second year in Engineering.I even had a lab in it.We used a book which had a Dinosaur picture in the front(i couldn't find out what similarity that the author found between a dino and operating system).It had a red cover.The author was Abraham Silberschatz.He explained all the concepts of Operating systems very clearly and in an enjoyable manner.So friends try to use that book as much as possible.