--- a/QScintilla/EditorMarkerMap.py	Wed Nov 05 19:28:50 2014 +0100
+++ b/QScintilla/EditorMarkerMap.py	Fri Nov 07 19:11:33 2014 +0100
@@ -26,6 +26,15 @@
         """
         super(EditorMarkerMap, self).__init__(parent)
         
+        self.setWhatsThis(self.tr(
+            """<b>Editor Map</b>"""
+            """<p>This shows a 'map' of the editor. The visible area is"""
+            """ highlighted by the box and all markers like bookmarks,"""
+            """ breakpoints, errors or changed lines are indicated"""
+            """ by differently colored lines configurable via the"""
+            """ Editor\u279dStyle page of the configuration dialog.</p>"""
+        ))
+        
         # initialize colors for various markers
         self.initColors()