Basically there are subheadings from 1 to 6, and the post title is heading level 1. So in content any heading start at level 2, which is H2. The later headings be H3, H4.
Why do we add this headings ?
Because it helps search engines like google to show rich snippet text using table of content and may help a user answer a query by matching keyword with your heading.
Headings also allow google to index your post in parts based on headings, so related and best matching part to be shown as a summary.
JACK
Basically there are subheadings from 1 to 6, and the post title is heading level 1. So in content any heading start at level 2, which is H2. The later headings be H3, H4.