In HTML headings are provided on levels, so that <h1> represents the first level heading while h2, h3, h4, etc. are smaller level headings:
Try the following example:
<h1>My Learning Plan</h1>
<h2>Learning HTML</h2>
<h3>The Page Structure</h3>
<h4>The title tag</h4>
The result will be something like:
Notice how each level differs in size. Now run the following example:
<!doctype html>
<html>
<head>
<title>My Learning Plan
</title>
</head>
<body>
<h1>My Heading 1
</h1>
<h2>My Heading 2
</h2>
<h3>My Heading 3
</h3>
<h4>My Heading 4
</h4>
<h5>My Heading 5
</h5>
<h6>My Heading 6
</h6>
</body>
</html>
The result will be something like:
Notes: