What is a “Dark Night of the Soul”?

People talk about this phenomenon all the time, but what does it really mean, and how do you know you are experiencing it?

I believe everyone experiences their “Dark Night (or month) of the Soul” differently, but the outcome is most often the same; a deep sense of clarity and a pervasive truth that you can’t ever forget. The “Dark Night” brings about a new way of seeing your life that you simply could not have seen before it happened.