How many types of headings do we have in HTML?

In HTML there are about six headings that start in html from <h1> ... and end at <h6>. Each heading of the HTML displays a different size. <h1> displays the largest heading size whereas <h6> displays least heading size.
For example: -

<h1> this is </h1> 
<h2> this is </h2> 
<h3> this is </h3> 
<h4> this is </h4> 
<h5> this is </h5> 
<h6> this is </h6>

Output

image.png