<h1> tag is missing
This means that the URL in question does not have a header 1 tag.
Why is this important?
The header 1 (h1) tag is considered important to help both users and search engines to quickly understand what content they can expect to find on the page.
If the h1 is not present, this represents a missed optimization opportunity.
What does the Hint check?
This Hint will trigger for any internal URL that has no <h1> tag in the HTML.
Why is this Hint marked 'Opportunity'?
In Sitebulb, this Hint is an Opportunity, as it represents a situation where you could optimize the site to potentially gain more search traffic.
There is some debate over the importance of the <h1> as an on-page ranking signal for SEO - however in most situations it is still considered a worthwhile optimisation tactic.