The GIMP Drawing Kit (GDK) is a computer graphics library originally designed for the
X Window System that wraps around low-level drawing and window functions. GDK acts as
the intermediary between Xlib and GTK+.
It renders drawings, raster graphics, cursors, and fonts in all GTK+ applications. Also,
since it is implemented in every GTK+ program, GDK provides drag-and-drop support and
GDK provides GTK+ widgets the ability to be drawn to the screen. To do this, every widget
has an associated GdkWindow object, except for a few widgets that will be discussed in a later
chapter. A GdkWindow is essentially a rectangular area located on the screen in which the widget
is drawn. GdkWindow objects also allow widgets to detect X Window System events.
GdkWindow objects also allow widgets to detect X Window System events.
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