Glade is a user interface-building program. It is used to rapidly prototype GTK+ and GNOME applications. It provides a framework that allows an application author to dynamically add, remove, and modify widgets. It is done in a very simple, yet powerful manner that lets even novice developers design a user interface in a short time.
While Glade can be used to generate both C and C++ code for use in your application, this is often not the best way to get the most out of Glade. Glade saves a user interface description to an XML file, and this can be dynamically used in your application using a library, libglade. By using libglade, you are left with more maintainable code, with a separation between the applications design and it's behavior. libglade is especially useful, because the XML file is loaded at runtime, allowing you to make tweaks to your user interface without having to recompile your application.