You can read more on link what I pointed to it. For me, Linux is a great operating system that I can use it as Desktop and Server. I have used it over ten years. It's very interesting operation system. I have used/worked it with many Open Source Software such as Apache HTTP, Bind, Sendmail, Postfix, Cyrus Imap, Samba and etc. It's operating system that I can play with programming languages as C, PHP, JAVA, Python, Perl and etc. I don't wanna say "too much".
Today, I have a chance to pick up some... a book that was written about Linux - How Linux Works, 2nd Edition What Every Superuser Should Know by Brian Ward. It's a cool book that you can learn about Linux as Starter and Linux Administrator. You could learn some things you have never used, but find in this book. It's fun to learn. However, A book, it's not support every skills in Linux. You will learn
- How Linux boots, from boot loaders to init implementations (systemd, Upstart, and System V)
- How the kernel manages devices, device drivers, and processes
- How networking, interfaces, firewalls, and servers work
- How development tools work and relate to shared libraries
- How to write effective shell scripts