When we generate the application using the Ionic CLI it generates the application structure to manage three tabs Dash, Chats and Account. Angular provides a main module as the core framework and the additional required functionalities are added via modules like the URL mapping and routing. In the app skeleton generated each one of the tabs is considered a view or a state (actually that are substates of a tab state) and each one is related to an URL. Angular provides generally two modules as options to manage the URL routing: Angular ngRoute and AngularUI Router. Ionic uses by default the ui-router.
These are the first steps, the initial commands and the index.html file you need to start developing your Ionic App with Firebase.