A look at the various forces in DOPs and how they work. This tutorial covers all the major forces except for the vortex, bouyancy and fluid forces. It covers both basic aspects and some more advanced techniques (animated masks, using RBD object position to drive a magnet force).   The final part looks at the magnet force, including how to animate it, and how to link its position to a rigid body that is being simulated. Finally we look at the most flexible of all the DOPs forces - the Field Force DOP. A project file containing some of the examples shown here is available from