01. What is XML?

This guide assumes you have a basic knowledge of how to read/write an XML document.
If you've never heard about XML, please access: https://www.w3schools.com/xml/

There you can find a very nice, really easy and efficient tutorial about it.
It is quite easy to learn and manage.
In fact, it's not even a programming language - it actually is a "bridge" between machine language and human language.