Some say XML does nothing. But actually none of these software does anything on its own, is it not always humans who do everything, at least until now?
"Solving the problem of universal data interchange between dissimilar systems," — Dr Charles Goldfarb.
XML is one of the out-of-sight niceties many websites incorporate and it provides magical services. DTD, XSLT, RSS, and more... Its usefulness is not limited to its capacity of handling data. Even tiny websites, such as mine, cannot afford not to have an XML sitemap.