> Before XML you had random binary or text formats, so APIs were a lot of work? Before XML there was, and still is, SGML. From W3C's XML spec: > The Extensibl

> Before XML you had random binary or text formats, so APIs were a lot of work? Before XML there was, and still is, SGML. From W3C's XML spec: > The Extensible Markup Language (XML) is a subset of SGML that is completely described in this document. Its goal is to enable generic SGML to be served, received, and processed on the Web in the way that is now possible with HTML. So XML was intended to simplify HTML/SGML syntax, and in the form of SVG, MathML, and XHTML (XForms etc.) to add new vocabularies and vocabulary evolution facilities to the web. There was this idea that your backend service produces XML payloads, and you transform that to HTML via XML transformation languages such as XSLT. Well, it's fair to say web frontend development took a different direction ;) but the initial idea was inspired by the web being a text/markup based environment rather than becoming a desktop replacement, which it eventually did for economic rather than technical reasons ie. nobody buying software hence only "service" lock-in was left to make a living from development (F/OSS played a role in this, too). From there, XML was then suddenly used for config files and everything else; not so much because it was a good fit, but because it sold well and was ending tool discussions in projects. There are numerous uses where XML wouldn't be today's choice for data exchange, but where XML is extremely useful and prevailing, even unlikely ones such as for exchanging 3D CAE models with Blender, but mostly enterprise and gov document and data exchange, because in 2000s and early 2010s the expectation towards "open" systems was higher, or just simply because the segment saw enormous growth during that time.