Start Glade from the Programs-->Development menu of the Gnome desktop (or else use Ctl+F2 and then type in glade to start the application). You will see three new windows popup. These constitute the Glade interface.
The left most window above is the main Glade window which will list the windows and dialogs of your own project. Currently it is empty. The middle window is the Palette window from where you choose the user interface widgets to include in your interface. The right window is the Properties window where you can edit the properties of each widget such as it's size, behaviour, and signals it responds to. There are two other Glade windows not shown but which can be displayed by selecting them from the main window's View-->Show Widget Tree and View-->Show Clipboard menus. We will see them later.