The GIMP ToolKit (GTK+) is a collection of GUI widgets. GTK+ essentially provides the building blocks from which GUIs can be built. It is highly themable, and its functionality is highly extensible. GTK+-2 is a very stable release, similar only in design to GTK+-1. GTK+-2 can coexist happily alongside GTK+-1, but applications are written for one version or the other. WWW: http://www.gtk.org/