I'm a practitioner myself, have had some interesting experiences including possessions, summonings, etc. Although things have quieted recently as I've settled down.

It is very much real, and the more you look into it, the more it will look into you. It's subtle, but is noticeable with the right sight. Best way I can describe what 'magic' is to the uninitiated is as a form of probability manipulation. Think of the world as one very large and complicated equation. The idea is that it only takes slight changes in a few numbers here and there to effect things on a much larger scale. These entities in other planes are not bound to all the same physical limitations as us (time, space, etc), and are able to alter reality in ways not fully understood.