The Headings tags defines the format and structure of a web document. There are six heading tags Separate on various sizes and thicknesses in HTML 5.The heading h1 has the largest and thickest text while heading h6 is the smallest and thinnest.
Heading tags always Start a new line in web pages
<h1>Heading 1</h1>
<h2>Heading 2</h2>
<h3>Heading 3</h3>
<h4>Heading 4</h4>
<h5>Heading 5</h5>
<h6>Heading 6</h6>
Example:
<h1>Main title page </h1>
<p>Introduction about page </p>
<h2>Post Title</h2>
<p>Post Excerpt </p>
<h3>Heading </h3>
<p>Paragraph</p>
<h3>Heading 2</h3>
<p>Paragraph</p>
<h3>conclusion</h3>
<p>Paragraph</p>