Check out example codes for "what is html used for". It will help you in understanding the concepts better.
Code Example 1
<!-- Answer to: "what is html used for" -->
<!--
HTML is used to create electronic documents (called "pages")
that are displayed on the World Wide Web.
-->
Code Example 2
Hypertext Markup Language is the standard markup language for documents
designed to be displayed in a web browser.
It can be assisted by technologies such as Cascading Style Sheets and
scripting languages such as JavaScript.
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