Q: Can you explain what an XML namespace is and how it's used?
A: An XML namespace is essentially a way of grouping XML elements together.
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, let's say that your XML document uses an element named "title" to contain the name of a book you are selling, while the other person's XML document uses the "title" element to contain a customer's name prefix (Mr., Mrs., Ms., Dr., etc.).
If you were to combine these XML documents, the data will become unclear and effectively meaningless because there are two "title" elements, and you wouldn't be able to tell them apart.
The solution to this problem is to group the element names from each XML document into its own namespace. Then, when referring to a particular element, it would be identified with the namespace in which it resides.
This provides a way to distinguish elements in one XML document from the other. For example, you could use the namespace “Products” for your XML document, and the other XML document's namespace could be called "Customers." The elements would then be referred to as "Products:title" and "Customers:title" respectively and would be clearly distinct.