Enneagram explained
The question is frequently asked: what exactly is the enneagram? Here I explain:
In a nutshell

The Enneagram is often called a personality typing system. The basic premise of which is that human personality traits can generally be grouped into nine categories. While it is certainly that, it is also much, much more.
While the Enneagram is a description of our preferred personality styles, it also provides for us a clear roadmap to the parts of ourselves that often remain hidden and underutilized. This can be a transformative process. A wise teacher, Ginger Lapida-Bogda describes it as "a study of the Human Ego Structures". This, to me, is the best descriptor I have found.
It is often said that the Enneagram "gets us out of the box that we have put ourselves into." Thus, it is the opposite of the assumption of many personality systems, in that it doesn't put you into a category, rather it helps to get you out of the one you might already be stuck in. Which is not to say that the teachings promote change for the sake of change--it clearly recognizes the gifts and strengths we all carry and present to the world.
Origins
The Enneagram philosophy and theory has shown up in various forms in writings going back for centuries. It was synthesized in the 20th century by a teacher in Chile, Oscar Ichazo, whose student Claudio Naranjo, an American psychiatrist, brought the teachings to the United States. It was developed into its most crystalized forms by a group of psychologists and spiritual masters in the 1970s. Many schools of study grew from there.
There is no copywrited version of the Enneagram. The study and evolution of this knowledge is fluid and brings forth current wisdoms and understandings, while keeping true to its most pure historical roots. One school of Enneagram study, The Narrative Enneagram, is based on just that: the narratives of individuals and their unique experience. There are certainly other valid schools, all of which I have drawn upon in my own study. But each of them, in my opinion, has some element of this narrative thread, which runs through the course of development of the teachings and particularly the expression of the philosophy.
Because no one corporation, institution or individual owns the Enneagram, the sharing of knowledge is very community