A webpage is a document and should be structured accordingly. Using the heading tags is a great way to structure your webpage and keep relevant information together.
A webpage should only have one H1 tag. Then you can have multiple h2, h3, h4, etc entries. However, my preferred option is to have one H1 and one H2. Then use multiple H3 for headings and H4 for sub headings. I never need to go beyond H4.
Always ensure that you keep the order! Never go H2 then H4, it must be H2 then H3. You can go H3, H4, H3.
So an example heading structure could be:
<h1>Main Heading</h1>
<h2>Content Heading</h2>
<p>paragraph</p>
<h3>Heading</h3>
<p>paragraph</p>
<h4>Sub Heading</h4>
<p>paragraph</p>
<h3>Heading</h3>
<p>paragraph</p>
This helps make the document more easily read and scanned for important information. If it's easier read by humans there's a good chance search engines will be able to read and understand it better too.
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