With the advent of JSON, and similar formats such as YAML, some hipster geeks have proclaimed that XML-based grammars no longer have any legitimate use. However, while I use JSON and YAML for many tasks, I still find XML (and related technologies such as DocBook 5, XPath, RELAX NG, and XSLT ) of use. Part of the reason is that XML can be used to add markup to a substring of the text (like the <a> element).