CREO interacts with Windchill PDMLink and Project-Link in the same manner. CREO needs to access files on your workstation and uses the local cache to interact with Windchill solutions. Each user below has a client machine with a  CREO or any supported CAD application installed. The CAD application is connected to the Windchill workspace or Work Group Manager. The green circles represent the server side workspace and the pink circles represent the client side workspace (local cache). All the changes and modification are made in the local cache using the CAD application when a model is checked out.