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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