an graphical alternative to writing scripts - Scripting for the GUI guys. A user can assemble a data processing 'machine' from 'gears' using drag-and-drop; select a data source; and run the machine to produce output.
a free user interface builder for GTK+ and GNOME interfaces designed are saved as XML, and by using the libglade library these can be loaded by applications dynamically as needed. (Glade can also generate C code)