Use for top-level heading
is the HTML element for the first level heading of a web document:
If the document is stand-alone, for example ‘Everything you want to know about SEO’, the top-level heading is probably the same as the title. If it is part of a collection, for example an introductory section on ‘SEO then and now’ in a collection of pages about ‘search engine optimisation’, then the top level heading should assume a certain amount of context; just write