“The Extensible Markup Language (XML), which just celebrated its 10th birthday 4, is one of the big success stories of the Web. Apart from basic Web technologies (URIs, HTTP, and HTML) and the advanced scripting driving the Web 2.0 wave, XML is by far the most successful and ubiquitous Web technology. With great power, however, comes great responsibility, so while XML’s success is well earned as the first truly universal standard for structured data, it must now deal with numerous problems that have grown up around it. These are not entirely the fault of XML itself, but instead can be attributed to exaggerated claims and ideas of what XML is and what it can do.” (Erik Wilde and Robert J. Glushko)