So What's A $#!%% Regular Expression, Anyway?!

Regular expressions, also known as "regex" by the geek community, are a powerful tool used in pattern-matching and substitution. They are commonly associated with almost all *NIX-based tools, including editors like vi, scripting languages like Perl and PHP, and shell programs like awk and sed. You'll even find them in client-side scripting languages like JavaScript - kinda like Madonna, their popularity cuts across languages and territorial boundaries...