What is the kingdom?

Another word that I hear thrown around a lot is "kingdom". Kingdom values. Kingdom living. Establishing His kingdom. This word is used by Christians to promote a lot of different political views, social responses, and even theological positions. Often opposing views are formed using this same word is the evidence that their view is correct.

My friend Aaron asks some questions about this.

I think that our understanding of the kingdom will have a great deal of affect on how we live and what we believe.

So what is Jesus talking about when he refers to the kingdom?

What does our understanding of the kingdom tell us about how we should live?