Heading Tag is < h1 >,< h2 >,< h3 >,< h4 >,< h5 >,< h6 >.
Header tags are very important in SEO because they are use to communicate to search engine about your content with this tag.
Header tags is not about how you format your text, eg : Color, Bold, Font Size.
It is about how you structure your content in a proper way so that reader and search engine able to identify which words are important.
The purpose of the heading tag is to structure your content with different heading tag so that it is more user friendly to user while reading.
Heading tag can tell the search engine which words are more important than the rest.
In your content, you need to follow the hierarchy structure of the heading tag from h1 (most important) to h6 (least important).
It supposes from h1->h6, once your skip h2 and proceed to h3, the heading structure is broken, it is consider not SEO friendly.
In one articles, we will only have one h1 tag, which normally is the main title of the post.
H2 tag will be the subheading; h3 tag will be the subheading under h2 subheading and so on. Example below.
Include your focused keywords in the h1 tag, but never stuff your heading tag with keywords.
Putting the focused keywords with h1 tag able to let search engine know this keywords is important.
Reference Article :
Do not use multiple h1 tag in your single web page.
When you do so, search engine might think you are trying to include more keyword for SEO sake.
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