You’ve learned how to create XML documents, transform, and display them, as well as define the set of elements and attributes that they can contain. Now, imagine that you want to combine some of your XML documents with someone else’s. In doing so, you find out that they have used some of the same names for elements that you have. For example, the Wonders of the World document uses the
name element to contain the name of each specific wonder, while the other person uses the
name element to contain the name of an ancient civilization. If I combine these XML documents, the source element data will become unclear and effectively meaningless.
The solution to this problem is to group the element names from each XML document ...