I'm learning about PHP and web coding.
Specifically, the PHP book I'm using that covers PHP 5.3 (by Matt Doyle and published by Wrox), says:
XML ... lets you create text documents that can hold data in a structured way...
XML isn't really a language but rather a sepcification for creating your own markup languages...
Wikipedia says of XML:
As of 2009, hundreds of XML-based languages have been developed,[8] including RSS, Atom, SOAP, and XHTML. XML-based formats have become the default for many office-productivity tools, including Microsoft Office (Office Open XML), OpenOffice.org and LibreOffice (OpenDocument), and Apple's iWork.[9] XML has also been employed as the base language for communication protocols, such as XMPP.
It sounds like XML is more like a protocol, a standard for allowing compuers to communicate and share information.
So XML is like a grammar I can use to create a markup language, but the language I create only formats data?
I want help defining the relationship between PHP and XML. When during the processesing of PHP and HTML does XML get parsed?