Creo Options Modeler > References > Data Management > Managing Parts and Documents > About Parts and Documents
  
About Parts and Documents
A part is an information object with an identification number, representing a physical component or assembly in a manufactured product.
Although a part can exist with or without a document, it is typically related to many document types, including CAD files.
A document is an object containing files in the application format. It has attributes and content that are relevant to the external application. A CAD Document is an object containing a CAD model that is a file or a set of files containing information in an application format. You can open a model in Creo and use the File > New CAD Document command to create a CAD Document.
CAD Documents serve the following purpose:
Store CAD-derived files (for example, 3D models, drawings, and viewable images).
Can be related to parts so that CAD Documents can describe the associated parts.
Can be related to other CAD Documents to allow the representation of the complex dependencies created and maintained by the authoring CAD system (for example, model-to-model and model-to-drawing relationships).
Contain the primary content (for example, a 3D CAD model file) and the secondary content (for example, a viewable representation of the 3D CAD model file).
For more information on creating a part and creating a CAD Document using the Windchill user interface, click in the Windchill HTML user interface