Systems help you create animations that would be much more difficult or time-consuming to produce using features independently. Systems can range from simple object generators to full-scale subsystem programs.
Systems are primarily intended for plug-in component software. Additional systems might be available if your configuration includes plug-in systems.
You can externally reference system objects in your scene. For more information, see XRef Objects.
To create a system:
Now the Object Type rollout displays different types of systems.