The HTML Heading element is placed above a section and specifies the topic of that section.
A Heading is usually a word or a phrase placed at the top of the page or paragraph and specifies the subject of that section.
<h1>This is a Heading</h1>
In HTML, the headings are created with the tags <h1> to <h6>. The content of the heading element is displayed in bold.
This rule should always be followed to display the most important subject with the h1 element. And show the less important subject with the h6 element.
This means that place the headings in order of importance in the elements h1, h3, ..., h6
<h1>This is Heading 1</h1> <h2>This is Heading 2</h2> <h3>This is Heading 3</h3> <h4>This is Heading 4</h4> <h5>This is Heading 5</h5> <h6>This is Heading 6</h6>