What is the main essence of using headings?

Question

HTML includes six levels of headings, which are ranked according to importance.
These are <h1>, <h2>, <h3>, <h4>, <h5>, and <h6>.

Answer 1

<h1> headings should be used for main headings, followed by <h2> headings, then the less important <h3>, and so on.

Headings are important for the Search Engine and for the users of your website.

"Use header for heading, not for make the text big and bold" (w3school) ^_^