diff --git a/pygadmin/widgets/main_window.py b/pygadmin/widgets/main_window.py
index 72e8fa0..a7331ed 100644
--- a/pygadmin/widgets/main_window.py
+++ b/pygadmin/widgets/main_window.py
@@ -555,11 +555,20 @@ class MainWindow(QMainWindow):
         self.command_history_dialog.get_double_click_command.connect(self.load_empty_editor_with_command)
 
     def closeEvent(self, a0: QtGui.QCloseEvent) -> None:
-        # TODO: Docu
+        """
+        Reimplement the close event of the main window and as a consequence, the close event of the whole application.
+        Check for unsaved files in the editor tabs, which could affect the close process.
+        """
+
+        # Check if the configuration for checking for unsaved files is not False, which means activated. Check also if
+        # there are open editor tabs, which are not saved. At this point, the user has been asked, if they want to stop
+        # the closing process and the check is True for that case.
         if global_app_configurator.get_single_configuration("check_unsaved_files") is not False \
                 and self.mdi_area.check_for_unsaved_editor_tabs() is True:
+            # Ignore the close event.
             a0.ignore()
             return
 
+        # Accept the close event and end the application.
         a0.accept()
 
diff --git a/pygadmin/widgets/mdi_area.py b/pygadmin/widgets/mdi_area.py
index e005851..899b45c 100644
--- a/pygadmin/widgets/mdi_area.py
+++ b/pygadmin/widgets/mdi_area.py
@@ -306,22 +306,35 @@ class MdiArea(QMdiArea):
         return None
 
     def check_for_unsaved_editor_tabs(self):
-        # TODO: Docu
+        """
+        Check for unsaved changes in the editor tabs of the mdi area.
+        """
+
+        # Introduce a variable for  unsaved changes. If there a unsaved changes, the variable is True, if not, False.
         unsaved_changes = False
 
+        # Get the list of editor widgets in the mdi area.
         editor_widget_list = [sub_window.widget() for sub_window in self.subWindowList()
                               if isinstance(sub_window.widget(), EditorWidget)]
 
+        # Check for every editor widget, if there are unsaved changes.
         for editor_widget in editor_widget_list:
+            # Check in the specific editor widget for unsaved changes.
             if editor_widget.check_for_unsaved_changes() is True:
+                # Warn the user and get the answer about closing anyway.
                 close_anyway = editor_widget.warn_about_unsaved_changes()
 
+                # If the user wants to close anyway, there are no unsaved changes.
                 if close_anyway is True:
                     unsaved_changes = False
 
+                # If the user does not want to close, there are unsaved changes.
                 else:
                     unsaved_changes = True
 
+                # Break the for loop, because there is now a result accepted by the user. All other potentially unsaved
+                # changes are checked with the previous check and user question.
                 break
 
+        # Return the result
         return unsaved_changes