diff --git a/app/code/backup/BackupAbstract.php b/app/code/backup/BackupAbstract.php
index 513ebbe..2d5884a 100644
--- a/app/code/backup/BackupAbstract.php
+++ b/app/code/backup/BackupAbstract.php
@@ -54,7 +54,7 @@ class BackupAbstract
      *
      * @return $this
      */
-    function addDate($format = 'Ymd')
+    public function addDate($format = 'Ymd')
     {
         $tmpFiles = array();
         foreach ($this->_filesToBackup as $file => $name) {
@@ -82,7 +82,7 @@ class BackupAbstract
      *
      * @return $this
      */
-    function addTime($format = 'his')
+    public function addTime($format = 'his')
     {
         $tmpFiles = array();
         foreach ($this->_filesToBackup as $file => $name) {
@@ -108,30 +108,6 @@ class BackupAbstract
 
     }
 
-    /**
-     * @param $folder
-     */
-    function backupToFolder($folder)
-    {
-        if (!empty($folder)) {
-            $folder = sprintf('%s/', rtrim($folder, '/'));
-        }
-//        if($folder != '')
-//        {
-//            if(substr($folder, 0, -1) != '/')
-//                $folder .= '/';
-//        }
-        foreach ($this->_filesToBackup as $file => $name) {
-            copy($file, $folder . $name);
-        }
-        foreach ($this->_streamsToBackup as $name => $file) {
-            if (count(explode('.', $name)) < 2) {
-                $name = 'backup' . $name . '.txt';
-            }
-            file_put_contents($folder . $name, $file);
-        }
-    }
-
     /**
      * Check if all files got the minimum given size.
      *
@@ -157,10 +133,7 @@ class BackupAbstract
     /**
      * @return bool
      */
-    public function isValid()
-    {
-        return true;
-    }
+    abstract public function isValid();
 
 }
 
diff --git a/app/code/backup/Folder.php b/app/code/backup/Folder.php
new file mode 100644
index 0000000..4870566
--- /dev/null
+++ b/app/code/backup/Folder.php
@@ -0,0 +1,22 @@
+<?php
+
+namespace Shikiryu\Backup\Backup;
+
+class Folder extends BackupAbstract
+{
+
+    public function __construct(array $config = array())
+    {
+        parent::__construct($config);
+
+
+    }
+
+    /**
+     * @return bool
+     */
+    public function isValid()
+    {
+        // TODO: Implement isValid() method.
+    }
+}
\ No newline at end of file
diff --git a/app/code/backup/Mysql.php b/app/code/backup/Mysql.php
index dee5271..c613262 100644
--- a/app/code/backup/Mysql.php
+++ b/app/code/backup/Mysql.php
@@ -90,6 +90,13 @@ class Mysql extends BackupAbstract
         return $return;
     }
 
+    /**
+     * @return bool
+     */
+    public function isValid()
+    {
+        // TODO: Implement isValid() method.
+    }
 }
 
 ?>
diff --git a/bu/newhtml.html b/bu/newhtml.html
deleted file mode 100644
index 6bd86f2..0000000
--- a/bu/newhtml.html
+++ /dev/null
@@ -1,14 +0,0 @@
-<!--
-To change this template, choose Tools | Templates
-and open the template in the editor.
--->
-<!DOCTYPE html>
-<html>
-    <head>
-        <title></title>
-        <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
-    </head>
-    <body>
-        <div>TODO write content</div>
-    </body>
-</html>
diff --git a/docs/using-scenario.md b/docs/using-scenario.md
index 30404ce..b973c55 100644
--- a/docs/using-scenario.md
+++ b/docs/using-scenario.md
@@ -1 +1,27 @@
-TODO
\ No newline at end of file
+Scenario is based on a json explaining how the backup will work.
+It contains 2 bases :
+  - backup (what you're going to backup)
+  - transport (how and where you're going to backup)
+
+# backup
+  - must begin with an uppercase
+  - a PHP class with the same name must exists in the Backup folder
+
+# transport
+  - must begin with an uppercase
+  - a PHP class with the same name must exists in the Transport folder
+
+# configuration of backup and transport
+  - all protected variable of the aimed class can be used as a configuration
+  
+# tips 
+## JSON
+The JSON must be compatible with the [PHP `json_decode`](http://php.net/manual/en/function.json-encode.php) implementation which correspond to [this one](http://www.faqs.org/rfcs/rfc4627.html)
+
+Basically :
+  - everything surrounded by " and no '
+  - no comments
+  - escape escape escape
+  
+
+
