GTK/GTK+ or Gimp ToolKit, is a GNU library for creating graphical user interfaces.

As implied by the name, the Gimp Toolkit was originally created for the GIMP image editor. It has since become one of the leading GUI toolkits for X, along with Qt, both of whom succeed Motif. GTK is generally favored by those who develop for Gnome, and Qt is favored for KDE. The reason for this is that GNOME uses GTK+ as a base toolkit, and KDE uses Qt.

GTK+ development

GTK+ is written in C, and provides bindings for C++ and Java, as well as the scripting languages Perl and Python (PyGTK). Other language bindings are available as well through third party bindings.

Developers using GTK+ can pick between various display engines that give GTK+ apps a wide variety of looks, from the old Motif style to the GTK+ standard look.

GTK+ applications are generally fairly portable, and can run outside of GNOME, on platforms such as Windows as well as KDE.

GTK+ 2

GTK+ 2 is the version 2 release of GTK+ that includes general improvements in many areas, but breaks compatibility with GTK+ 1. These improvements include better support for Unicode, accessibility improvements, and changes to the API to improve flexibility. These improvements however come at the cost of speed and simplicity, and many developers continue to use GTK+ 1.