MacOS X’s unix underpinnings have had Mac users asking the same question for a while now: “how can I learn Unix?” And for those who really want to learn Unix, I point them to ?leenFrisch’s <a href=“http://www.oreilly.com/catalog/esa3/" title=“Essential System Administration, 3rd Edition“>Essential System Administration, 3rd Edition.
It’s direct and concise, yet thorough. It was the book I turned to for an introduction to Unix, and it’s a book I keep on my shelf as a reference when I need it.