Hi there,
good question 🙂 The design term refers to what normally is Large Image with some content over it such as a Title or Call to Action you see below the Site Header / Navigation on a site. But those designs vary from site to site.
In GPP we have header elements that allow you to create them dynamically:
https://docs.generatepress.com/article/header-element-overview/
The advantage of those is you create a single header element, that displays the featured image as a background and can include the post title / post meta ( as well as other stuff ) and dynamically display this across your site. So one header element can be created that will be dynamic for all your Posts for example.