AWK: a powerful tool for programmer

Introduction

AWK is an acronym of first letters of its authors (Aho, Weinberger and Kernighan). It is a data-manipulating scripting language with huge possibilities. There are several implementations of it: awk is a canonical one, nawk (new awk), mawk (default in Ubuntu 12.04), gawk is GNU awk. I recommend latter one, because it works correct with unicode symbols in example:

$ echo юникод | gawk "{res = toupper(\$1); print res;}"
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