Awk (and Gawk, the GNU alternative) are as old as the hills (well, as old as Unix) and remain as one of the original programmable elements of the Unix operating system, along with the various shells (Bourne shell, Korn shell and C shell, in the original Unix editions).
I’m a tester of Gawk, responsible for checking the compatibility of new releases on different platforms, a job I first started when working on the BeOS and which I now do for Mac OS X, various Linux alternatives, Solaris SPARC and Intel and any other environment I happen to have available.
Awk is actually an incredible powerful programming language, although it is better known for many text processing tasks as an alternative to using the cut and paste tools or similar shell-level commands. The problem is many people don’t know it exists, even though vast quantities of the Unix/Linux scripts and other tools use awk/gawk for a variety of different tasks.
There’s a good introduction to using awk/gawk for text processing at Linux.com: Learning to talk awk.