If you don't believe in any gods, you are an atheist, right? This definition seems pretty basic, not the kind of material that requires an advanced degree in theology to understand.
But apparently it isn't accurate. In fact, as I circulate in the secular movement on a daily basis, I frequently meet nonbelievers who are unwilling to identify as atheists.
MORE: http://www.psychologytoday.com/blog/our-humanity-naturally/201206/nonbelievers-who-arent-atheists