What is a hacker?

The best overview is PG's essay: "The Word 'Hacker'"

You can read it at: http://www.paulgraham.com/gba.html

As far as finding one....you're in the right place. However, there is a theory that only an accomplished Hacker can truly recognize another Hacker. So unless YOUR a Hacker...how will you know?

I am starting a new start up and the domain is YouYap.com. I post it here and people break into it. So I am looking to find someone to joint me in this project. How do I find the best hacker?