Besides the obvious difference of a few letters HTML and XML are quite different.
First, there’s HTML. It caught on in the early 90s as a way to build web pages. HTML stands for Hypertext Markup Language for this very reason–it was designed to display data, focusing on how the data looks. All of the pages that you look at on the web are made of some sort of HTML. HTML tells the browser what colors to use, where to place the images, what the words are on the page etc…
The content in HTML is wrapped in tags. Tags have a start tag and an end tag and are wrapped in brackets <>.
XML stands for Extensible Markup Language, and yes, that starts with an E, not an X. XML also uses tags. Unlike HTML, the tags are created by the one writing the XML. XML is used often to store data in a logical format. XML was designed to carry and store data, with a focus on the data’s content.
If you have an HTML file and open it in a browser, you will see something. But if you open an XML file in a browser, you will see just code. XML doesn’t do anything. It needs additional software or code to be used.