Over the weekend XML 1.0 turned 10 years old from the day it was first accepted as a W3C recommendation. It started as a subset of SGML that allowed generic document content to be served and processed over HTTP. It's now used for everything, including the kitchen sink.

XML 1.0 included a number of quirks, such as a large and complicated language production that created a custom subset of Unicode for defining names. XML 1.1 tried to fix these quirks but broke compatibility in the process, leading to its virtual death due to lack of adoption. The world still works off of XML 1.0. That's why last week a new proposed recommendation came out to define a Fifth Edition of XML 1.0.