The ABAP Element Info in ADT is a central, but often underestimated feature. It provides read-access to all kinds of elements.
You can use it as popup window, as permanent view and also as part of the code completion feature.
Element Info can be triggered with F2 for any identifier inside source code editors.
Element Info View (Permanent, Link with Selection)
The Element Info View can be used to permanently display element info. This is especially useful with the “link with selection” feature.
Code Completion (Side Window)
The Element Info is also displayed as sidekick of the code completion. This provides additional information about the particular completion proposal.
If you want to see the Element Info in action and are willing to learn all the interesting details, I strongly recommend to watch the following video.