May 26, 2018
Gimp Toolkit for X11 GUI (current stable version)
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+-3 is a very stable release, similar only in design to GTK+-2. GTK+-3 can coexist happily alongside GTK+-2, but applications are written for one version or the other.