XML (eXtensible Markup Language) is a software and hardware independent tool for storing and transporting data, and it is designed to be self-descriptive. XML is a markup language.
XML is a W3C Recommendation.
There are 5 pre-defined entity references in XML:
<: < (less than)
>: > (greater than)
&: & (ampersand)
': ' (apostrophe)
": " (quotation mark)
JSON became a very common format, many programming languages include code to generate and parse JSON-format data.