--- a/classes/basemodel.php	Tue Apr 21 16:41:36 2015 +0200
+++ b/classes/basemodel.php	Thu Apr 23 14:58:27 2015 +0200
@@ -1,7 +1,31 @@
 <?php
+/* basemodel.php
+ * This file is part of Extraction-interface.
+ *
+ * Extraction-interface is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Extraction-interface is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Extraction-interface.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
 /**
-* BaseModel is for the general methods/functions.
-* For example, setting related to outside services, connecting to database, get information from database, etc.
+ * A model is notified by its associate controllers when there has been a change in its state,
+ * and produces the output/data to corresponding views.
+ *
+ * (http://en.wikipedia.org/wiki/Model–view–controller)
+ * 
+ * There are general methods/functions.
+ * For example, setting related to outside services, connecting to database, get information from database, etc.
+ * For other methods that are more related to each application, are defined in the files under "models/" folder.
+ * 
 */
 
 abstract class BaseModel {