In my journey to make an examples-based user-friendly awk the series (as a pair of sed the series). It’s because finding user-friendly practical examples of awk is difficult.
http://www.grymoire.com/Unix/Awk.html (my favorite so far)
http://www.bolthole.com/AWK.html (Part 1-6)
https://www.ibm.com/developerworks/library/l-awk1 (Part 1-3, Daniel Robbins)
http://www.folkstalk.com/2011/12/good-examples-of-awk-command-in-unix.html (Folkstalk was my only inspiration to write sed the series; Folkstalk successfully convinced me that trying sed is easy)
http://www.pement.org/awk/awk1line.txt (my first time was sedoneliners but this one is very similar)
http://www.catonmat.net/blog/awk-one-liners-explained-part-one (Part 1-3; I just found tonight and it’s very good)
https://www.eriwen.com/tools/awk-is-a-beautiful-tool (this article inspired catonmat’s one)