What is Heading ?
HTML provides not only plain paragraph tags, but six separate header tags to indicate headings of various sizes and thicknesses. Enumerated as heading 1 through heading 6, heading 1 has the largest and thickest text while heading 6 is the smallest and thinnest, down to the paragraph level. This topic details proper usage of these tags.
Section 3.1: Using Headings
Headings can be used to describe the topic they precede and they are deﬁned with the <h1> to <h6> tags. Headings support all the global attributes.
<h1> deﬁnes the most important heading.
<h6> deﬁnes the least important heading.
Deﬁning a heading:
- <h1>Heading 1</h1>
- <h2>Heading 2</h2>
- <h3>Heading 3</h3>
- <h4>Heading 4</h4>
Correct structure matters
Search engines and other user agents usually index page content based on heading elements, for example to create a table of contents, so using the correct structure for headings is important.
In general, an article should have one h1 element for the main title followed by h2 subtitles – going down a layer if necessary. If there are h1 elements on a higher level they shoudn’t be used to describe any lower level content.
Example document (extra intendation to illustrate hierarchy):