Because the COBOL information model can largely be expressed by the XML information model, there is a natural relationship between XML documents and COBOL data structures. Both present similar views of the data; that is, the entire data is visible. You may view the content of a COBOL data record and you may view the text of an XML document. In XML, markup is used both to name and describe the text elements of a document. In COBOL, the data structure itself provides names and descriptions of the elements within a document.

XML Extensions has many capabilities. The major features support the ability to import and export XML documents to and from a COBOL program's Data Division. Note that data may be anywhere in the Data Division. Specifically, XML Extensions allows data to be imported from an XML document by converting data elements, as necessary, and storing the results into a matching COBOL data structure. Similarly, data is exported from a COBOL data structure by converting the COBOL data elements, as necessary, and storing the results in an XML document.

XML Extensions consists of the following main components: