What is CrossFit?

Have your friends started asking you about CrossFit yet? When you go to work after a WOD, barely able to lift your arms, do people ask you what in the world you're doing? How do you explain it to them?

It can be pretty difficult to sum up CrossFit in just a few sentences. In fact, my answer usually ends with, "Just come check it out and see for yourself." I submit for you some resources for sharing with others, or for your own personal knowledge, to answer the question: "What is CrossFit?"