Forgive and ignorance and stupidity, but what is the difference?? [&o]

3D is a type of flying. Which is usally slow and controlled. Most of the time the wings are stalled and lift is generated mostly from the prop.

Freestyle is the routine you fly in either in competion or practice, which is usually a mix of 3D and precision. In IMAC you must fly precise moves. In freestyle it's more like .... show us what you got.

Freestyle uses defined criteria. It can and usually does involve 3-D maneuvers along with precision and choreography.
Fred