Headings Get Attention
Aren't We Suppose to Write for Readers?
What are HTML Header Tags?
Standard HTML header tags are as follows - <h1>, <h2>, <h3>, <h4>, <h5>, <h6>. Simply, their sizes are different. They are meant to use in different levels. For example, <h1> tag used for top-level headings. Under that <h2> headings. Next level is <h3> and so on. Below you can see how they are looks like.
Though <h1> is used for top-level headings, in blogging and writing online, <h1> tag would be used for post or article title as a standard. So headings used in the content would start with <h2> header tags and you can use up to <h6>. Obviously you can change sizes of header tags if you need to.
If you are in Blogger blogging platform, you can easily define header tags for headings without manually tagging them. Use heading options in Blogger Post Editor and your headings will tag automatically. Here's available heading options in Blogger.
Heading - This option will tag your heading with <h2> header tag
Subheading - This option will tag your heading with <h3> header tag
Minor heading - This option will tag your heading with <h4> header tag
Benefits of Using HTML Header Tags
The use of HTML header tags for your headings would be helpful for search engine bots to index your pages in structured manner. Once bots identify your headings defined with header tags, they will assume your headings represent content beneath them. So as search bots index your pages in structured manner while noticing headings you have been using, search engines could serve better for web searchers. So it will be a plus point in SEO too. However if you don't use header tags for headings, search bots will just treat them as normal text.
Abuse and Misuse of Headings
Though usage of headings has a SEO value, just don't start to use headings in each of your posts or articles blindly. Use headings to structure and guide your readers through the post or to get attention. You can experiment with that, but don't abuse it. Make sure you are adding value to your content with headings.
I haven't seen misusing of header tags yet. Anyway, don't use header tags for any other purposes. Don't use them with normal text to emphasis somethings. In that case, you can use some styles or different font sizes. Just use HTML header tags for your headings only.