Headings are defined with the <h1> to <h6> tags, and their elements are written as <h1>...</h1>.

<h1>This is a Heading 1</h1>

Compare this to Markdown:

# This is a Heading 1

<h1> defines the most important heading. <h6> defines the least important heading.

<h1> headings are considered to be main headings, while <h2> headings are usually considered sub-headings and so forth, through <h6>.

Note By default, browsers will display headings with decreasing font size, although headings should instead be explicitly styled using CSS rules and definitions. This prevents any un-expected rendering of the web document content.

html elements markdown headings tags