GTK+(GIMP Tool Kit) is one of the most widely used ToolKit for creating graphical user interfaces(Originally for X-Window).It is designed to be small,flexible and efficient and offers complete set of widgets;hence it is suitable for projects from small to complete application suites.So basically it is a collection of some libraries so that you can use them to create GUI’s for your programs or applications.
Installing GTK+ in Ubuntu 10.04
1.You can install the GTK+ libraries from Synaptic Package Manager.Open Synaptic Package Manager.
2.Search for GTK+,then select the libraries you want e.g libgtk 2.0-dev.. then mark for installation.
3.Now you can click on Apply to install the selected libraries or packages.
4.It will take few minutes to download and install the GTK+ library-packages.Wait until the installation will complete.