Found in 3 comments on Hacker News
vram22 · 2015-10-02 · Original thread
Check out this book: The Linux Command Line.

There's a review of it by me on that page, under the Reviews link. I think that review (which I spent some time and effort writing) will give you a fairly good overview of the topics you (or anyone) needs to learn to become good at using Linux (or other Unixes) at a user level.

There are also tons of other resources for it on the net, including many at - The Linux Documentation Project. Some of those may feel more advanced, so you may want to start with the book above, or any other similar book, and then move on to the TLDP and other tutorials on the net.

vram22 · 2015-02-21 · Original thread
Yes, that book is good. I had reviewed it for O'Reilly, a while ago, here:

2nd review from the top (currently), reviewer id is vasudevram.

vram22 · 2014-01-10 · Original thread
Yes, that one is good. I reviewed it here for O'Reilly:

Mine is the 2nd review from the top, currently; the one titled "A useful book for beginners to Linux".

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