HTML heading tags are defined with the <h1> to <h6> tags. <h1></h1> tag is giving the biggest font size among the heading tags. Usually, the font size of the header text decreases from tag <h1> to <h6>.
The following example shows the simple HTML program structure which uses these different HTML header tags separately.
<!DOCTYPE html>
<html>
<head>
<title>
HTML PROGRAMING TUTORIALS - HEADING TAG
</title>
</head>
<body>
<h1> This is the h1 header </h1>
<h2> This is the h2 header </h2>
<h3> This is the h3 header </h3>
<h4> This is the h4 header </h4>
<h5> This is the h5 header </h5>
<h6> This is the h6 header </h6>
</body>
</html>