GTK+

GTK+ is the primary library used to construct user interfaces in GNOME. It provides all the user interface controls, or widgets, used in a common graphical application. Its modern, object-oriented API allows you to construct attractive and sophisticated user interfaces without dealing with the low-level details of drawing and device interaction.

In addition to basic widgets, such as buttons, check boxes, and text entries, GTK+ also provides powerful Model-View-Controller (MVC) APIs for tree views, multi-line text fields, and menu and toolbar actions.

Widgets in GTK+ are placed on windows using a box-packing model. Programmers specify only how to pack widgets together in container boxes, rather than position them directly with absolute coordinates. GTK+ ensures that windows are sized correctly to fit their contents, and it automatically handles window resizing.

Because GTK+ offers a flexible API, developing additional widgets for use in GTK+ applications is easy. A number of third-party libraries exist which provide additional widgets, and many developers have created custom, special-purpose widgets for their applications.

GTK+ handles the difficult details of user interfaces and user interaction, and provides a simple yet powerful API which allows you to focus on the details of your application. Applications developed with GTK+ will automatically follow the user's theme and font settings, will interact properly with accessibility technologies, and will behave as users expect.