Groups of Operators

    * SOP = Surface OP (3D = geometry modeling)
    * POP = Particle OP
    * SHOP = Shader OP
    * COP = Composite OP (2D = compositing, image processing)
    * CHOP = Channel OP (1D = channels, mocap, audio, logic)
    * VOP = Vex OP (VEX = Vector EX-pression language, shaders, custom operators of any type)
    * ROP = Render OP (outputs for all data types)
    * DOP = Dynamics OP (simulations, dynamics solvers)