Anchor Point is the model's "handle" for being positioned, rotated, and scaled. All movements will revolve around the Anchor Point position. If the model has an anchor point that is far away from the model, when rotating the model it will swing very wide. If the anchor point is more centered to the object, it will rotate more centered around itself. Moving an anchor point can be helpful when needing to rotated helecopter rotors, car wheels, or anything that needs a central rotation.
Anchor Points are exported from the 3d program that the originally came from. In a full 3d application, an object will have many anchor points as there are many pieces that can make up an object. But in Element the model comes in as one piece. So Element will use the World Anchor point from the the program it was exported from. So if the model was off center in the 3d program, once exported the anchor point will be off center in Element. If the object was at 0,0,0 center in the 3d program, the anchor point will come in centered in Element.
Notice how in C4D the model is far above from the
world center anchor position.
Once you import that into Element, and change the Anchor
Position to From Model, you will notice that the Anchor Point
is in the same location as the world center anchor
point from C4D.