Around 2000 or so, I used to work in tech support for a software company who had like 5000 Windows-based customers and 5 running Solaris. My boss chose me to learn Solaris when the previous "expert" left. I bought this book and started hacking. Good times!
From Wikipedia, the free encyclopedia
Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).
Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.
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I have/had a bunch of these books. Some got lost but I have the electronic versions of them.
This is one other book I fondly remember. UNIX For Application Developers. From 1991 I think. I vaguely remember a statement in the intro along the lines of Windows being user friendly but UNiX being expert friendly. :-)
Couldn't find a better image.