XML was not designed to DO anything.
XML was created as a platform neutral way to Structure, Store and Transmit data.
XML provides a cross platform, machine independent method to allow B2B (Business to Business) exchange of information.
As such it will form the backbone of e-commerce.
It forms the basis of Microsoft's .NET strategy and many other companies software development.
The internet and your computer is awash with various xml files.
Try a search for files ending in .xml on your computer.
What's more there are many files which are xml but have a different extension.