Yes Designer ribbon is related to sub tabs,While the ribbon represents a new way of organizing and presenting the controls within SharePoint, in general, the controls themselves have changed very little from previous versions. All of the original functionality that you may be used to is still there, but presented in a different way.
At the top of the ribbon are a series of tabs which relate to the different kinds of functions that can be performed within a given page. For example, when you open the default page for a list or library, the page opens with the Browse tab selected. The Browse tab has no ribbon-based tools associated with it. Depending on your level of permissions and the type of page you are viewing, other tabs, such as Edit, Share & Track, Publishing, and List Tools or Library Tools may appear as well. To use the ribbon controls, click the tab that corresponds to the kind of task you want to perform.