Mapping is the process of relating the structure, values, or content of a business document in one format to the values and fields in an alternate business document format. You need to create maps between business documents because, for example, your internal (back-end) system may render data in a different format than that of the RosettaNet PIP documents. Transforming a document generated by your back-end system into RosettaNet format allows you to exchange data with your partners in a common format.