This part of ISO 13584 specifies a representation category, called ISO10303_rep. This representation category captures the generic concepts used to describe the representation of a product in ISO 10303 application protocols. This representation category may be associated with any of the items defined in a parts library. This part of ISO 13584 also defines how representations that belong to this representation category may be exchanged within a library exchange context by means of ISO 10303 compliant data repositories. The following are within the scope of this part of ISO 13584: — the definition of the ISO10303_rep representation category, and the mechanisms that are to be used to reference it; — the properties used to characterize a particular representation within the ISO10303_rep representation category; — the implementation resources to be supported by any implementation that claims conformance to this part of ISO 13584; — the dictionary entries to be supported by any implementation that claims conformance to this part of ISO 13584; — the standard data to be recognized by any implementation that claims conformance to this part of ISO 13584. The following are outside the scope of this part of ISO 13584: — the structure and exchange format of library delivery files; — the structure and exchange format of library external files that conform to ISO 10303 application protocols.