Navigate and organize the workspace
The Explorer is the workspace as a tree: domains, the subdomains nested under them, and the services inside those. What you pick in it is the scope, and the rest of Compass works on it: search looks there, new issues and notes are filed there, and its policy says how its work runs. One search reaches everything in the scope — its functions, its issues and the text of its files — as well as every service and domain, and command mode opens any of them in the Viewer without leaving the keyboard. In edit mode, folders you already have join a domain where they sit; nothing on disk moves.