Linux GUI Frameworks and Widget Toolkits Explained
Linux GUI toolkits might sound confusing, but they define the look and feel of modern Linux desktops. Here's everything you need to know about them.
The X Window System is the main display server in use on Linux desktops today. While it may provide elements of a graphical interface, it doesn’t supply any user interface elements by itself. This is a deliberate design choice on the part of the original developers.
X doesn’t know how to draw window decorations. It doesn’t draw the buttons in windows or lay out any text elements. All of these things are handled by the toolkit.
X toolkits offer developers a way to define graphical elements without having to do it all manually. Instead of writing out code to allow users to pick files from a dialog box, they can farm this out to a library instead.