title: How a RegEx engine works
body: <p>In learning Regular Expressions it had me wondering how the underlying engine works.  Probably more specifically, I'd like to know more about how it evalutates, prioritizies and parses the expression.  I feel the RegEx engine is a blackbox to me, and I would really enjoy deciphering it.</p>
  
  <p>So I'd like to ask if there are some great resources that I could read up on that discuss RegEx engine theory.</p>
  
  <p>*Note:  I am not interested in building an engine, just learning the inner workings of it.</p>