[gtk+] Introduction explaining widget toolkit

[Bastian Ilsø Hougaard <bastianilso src gnome org>]

commit f3d95d05eb599c80327db0b7c318d60818b48609
Author: Bastian Ilsø <bastianilso src gnome org>
Date:   Tue Jan 27 11:43:40 2015 +0000

    Introduction explaining widget toolkit

 docs/reference/gtk/getting_started.xml |   15 +++++++++++++++
 1 files changed, 15 insertions(+), 0 deletions(-)
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diff --git a/docs/reference/gtk/getting_started.xml b/docs/reference/gtk/getting_started.xml
index 892425b..8644ef8 100644
--- a/docs/reference/gtk/getting_started.xml
+++ b/docs/reference/gtk/getting_started.xml
@@ -5,6 +5,21 @@
 <chapter id="gtk-getting-started" xmlns:xi="http://www.w3.org/2003/XInclude";>
   <title>Getting Started with GTK+</title>
 
+  <para>GTK+ is a <ulink url="http://en.wikipedia.org/wiki/Widget_toolkit";>
+  widget toolkit</ulink>. Each user interface created by 
+  GTK+ consists of widgets. This is implemented in C using 
+  <link linkend="gobject">GObject</link>, an object-oriented framework for C.
+  Widgets are organized in a hierachy. The window widget is the main container.
+  The user interface is then built by adding buttons, drop-down menus, input 
+  fields, and other widgets to the window.
+  If you are creating advanced or complex user interfaces it is recommended to
+  use #GtkBuilder and its GTK-specific markup description language, instead of
+  assembling the interface manually. You can also use a visual user interface
+  editor, like <ulink url="https://glade.gnome.org/";>Glade</ulink>.</para>
+  
+  <para>GTK+ is event-driven. The toolkit listens for events such as
+  a click on a button, and passes the event to your application.</para>
+
   <para>This chapter contains some tutorial information to get you
   started with GTK+ programming. It assumes that you have GTK+, its
   dependencies and a C compiler installed and ready to use. If you