Header 1 tags, known as H1 Tags are meant to serve as the headline of your website in HTML.

They appear in the largest & boldest font of all header tags by default. They are important for SEO as the keywords contained in them are considered to be 3rd highest importance by search engines when crawling your content (following URL & Title Tag).

H1 tags are only allowed to be used once on a page & are meant to add more detail to your pages main keywords from the URL & Title Tag.

Search Engines will use consider up to 80 characters of text in this field traditionally. 

Well-Optimized H1 Tags Are Essential For Your Webpages

H1 Tags are not just useful for catching the eye of your user’s as a page’s headlines.

When a bot parses them, it looks as the H1 tag’s content to be an extension of the keywords in the URL & Title Tag, which are the ones it deems most important in relation to the rest of the page’s content.

Always research keywords before constructing H1 tags for a page, and ensure that the keywords being used complement the other keywords, as well as the rest of the page’s content.

Improper use of keywords in H1 tags is one of the easiest mistakes to correct from an SEO & ranking perspective, making them a low-hanging fruit optimization.