@Judi, yeah, what lifeflame said. I was going to give you almost the same answer, down to the music analogy.
Many people are are not aware that there is underlying structure to much human activity. Conversations have structure (sometimes structure appears as rules), but we hardly ever acknowledge it, and when we do, we refer to it as ettiquette.
If I tell you to focus on your feet, and dance with your feet leading and the rest of your body following, I’ve given you a structure in which to improvise. If I tell you to “speak” to another dancer with your feet, I have added an addictional constraint (structure) within which you must figure out how to move.
By focussing dancers in this way, we help – well, anyone – you don’t have to be a dancer at all. You don’t need any dance experience at all. It’s really a movement workshop, and yet, out of this inexperience arises some incredible dances that no one could ever choreograph!
What happens is that you learn a movement/dance vocabulary over the course of an hour or so, which in the last 45 minutes you use to choreograph your own dance, as you dance it. It’s all done without stopping, and only a few instructions here and there.
There’s also live, improvised music, and one of the cool things is that the musicians structure is the dancers. Essentially, they are the chart for the musicans. We play to support them, and to lead them, and after a while it is unclear as to who is leading whom.
We live in a web of hidden structure, within which we improvise our lives. It is the same thing as a poet choosing to constrain their poem by using the sonnet form, or the sestina.
Ah well, I could go on for days about this, but I shall spare you the inner working of my corporeally-informed philosophy.