The diagram view displays groups for the activated integrations (Amazon / Azure). From here you can drill into them by expanding the groups or by clicking on their icons to view high level information.
Top Left - Search bar
Top Right - Dashboard button - Navigate to the 'Dashboard' View.
Top Right - Diagram Controls (from left to right):
Home - Resets to this initial view and pre-selects one of the groups shown above.
Center - Centers the current diagram to fit the screen
Expand-All - Expands a selected group and all of it's sub-groups (all the way down).
Isolate - Isolate a piece of the diagram in different ways
Views - VIew the diagram 'for' a particular tag.
Links - Toggle between showing links in their 'individual' or 'grouped' state
Show/Hide - Adjust the visibility of different types of resources
Center - Datasource Groups