Index: for_developers/Sphinx/source/Documentation/Overview/app_modes.rst
===================================================================
--- for_developers/Sphinx/source/Documentation/Overview/app_modes.rst	(revision 41c9dbc9816a48a73dd439140ea7f56de10d8f43)
+++ for_developers/Sphinx/source/Documentation/Overview/app_modes.rst	(revision 41c9dbc9816a48a73dd439140ea7f56de10d8f43)
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+*****************
+Application Modes
+*****************
+
+.. role:: underline
+    :class: underline
+        
+.. _member state: https://www.ecmwf.int/en/about/who-we-are/member-states 
+.. _instructions: https://apps.ecmwf.int/registration/
+
+    
+.. _ref-app-modes:
+
+Arising from the two user groups described in :doc:`../../Ecmwf/access`, ``flex_extract`` has 4 different :underline:`user application modes`:
+
+.. _ref-remote-des:
+
+  1. Remote (member)
+      In the **Remote mode** the user works directly on ECMWF Linux member state server, such as ``ecgate`` or ``cca``. The software will be installed in the ``$HOME`` directory. The user does not need to install any of the additional third-party libraries mentioned in :ref:`ref-requirements` as ECMWF provides everything with environment modules. The module selection will be done automatically in ``flex_extract``. 
+      
+.. _gateway:
+      
+  2. Gateway (member)
+      The **Gateway mode** can be used if a local member state gateway server is in place. Then the job scripts can be submitted to the ECMWF Linux member state server via the ECMWF web access tool ``ecaccess``. The installation script of ``flex_extract`` must be executed at the local gateway server such that the software will be installed in the ``$HOME`` directory at the ECMWF server and some extra setup is done in the local ``flex_extract`` directory at the local gateway server. For more information about establishing a gateway server please see section ???. For the **Gateway mode** the necessary environment has to be established which is described in :ref:`ref-local-prep`.
+
+.. _local:
+      
+  3. Local member
+      Scripts are installed and executed on a local machine, either in the current ``flex_extract`` directory or in a path given to the installation script. Under this scenario a software environment similar to that at ECMWF is required. Additionally, Web API's have to be installed to access ECMWF server. The complete installation process is described in :ref:`ref-local-prep`.
+      
+  4. Local public
+      Scripts are installed and executed on a local machine, either in the current ``flex_extract`` directory or in a path given to the installation script. Under this scenario a software environment similar to that at ECMWF is required. Additionally, Web API's have to be installed to access ECMWF server. The complete installation process is described in :ref:`ref-local-prep`. In this case a direct registration at ECMWF is necessary and the user has to accept a specific license agreement for each dataset he/she intends to retrieve. 
+      
+      
+An overview is sketched in figure :ref:`ref-fig-marsaccess`.
+
+.. _ref-fig-marsaccess:
+
+.. figure:: ../../_static/Diagramm_MarsAccess2.png
+
+   Application modes 
+
+
+    
+.. toctree::
+    :hidden:
+    :maxdepth: 2
Index: for_developers/Sphinx/source/Documentation/Overview/convert.rst
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--- for_developers/Sphinx/source/Documentation/Overview/convert.rst	(revision 41c9dbc9816a48a73dd439140ea7f56de10d8f43)
+++ for_developers/Sphinx/source/Documentation/Overview/convert.rst	(revision 41c9dbc9816a48a73dd439140ea7f56de10d8f43)
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+=======
+CONVERT
+=======
+
+ 
+    UNDER CONSTRUCTION
+    
Index: for_developers/Sphinx/source/Documentation/Overview/prog_flow.rst
===================================================================
--- for_developers/Sphinx/source/Documentation/Overview/prog_flow.rst	(revision 41c9dbc9816a48a73dd439140ea7f56de10d8f43)
+++ for_developers/Sphinx/source/Documentation/Overview/prog_flow.rst	(revision 41c9dbc9816a48a73dd439140ea7f56de10d8f43)
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+Program Flow
+================
+
+ 
+    UNDER CONSTRUCTION
