+\subsection overview_kernel Simulation kernel layer
+
+The core functionnalities to simulate a virtual platform are provided by a
+module called <b>\ref SURF_API</b>. It is
+very low-level and is not intended to be used as such by end-users. Instead,
+it serve as a basis for the higher level layer.
+
+SURF main features are a fast max-min linear solver and the ability to
+change transparently the model used to describe the platform. This greatly
+eases the comparison of the several models existing in the litterature.
+
+See the \ref SURF_API section for more details.
+
+\subsection overview_fondation Base layer
+
+The base of the whole toolkit is constituted by the <b>\ref XBT_API
+(eXtended Bundle of Tools)</b>.
+
+It is a portable library providing some grounding features such as \ref
+XBT_log, \ref XBT_ex and \ref XBT_config. XBT also encompass
+the following convenient datastructures: \ref XBT_dynar, \ref XBT_fifo, \ref
+XBT_dict, \ref XBT_heap, \ref XBT_set and \ref XBT_swag.
+
+See the \ref XBT_API section for more details.
+
+
+\htmlonly <!-- ______BODY_BEGIN______ --!> \endhtmlonly
+<br>
+The SimGrid software package can be downloaded from
+<a href="https://gforge.inria.fr/frs/?group_id=12">here</a>.<br>
+
+If you are interested in the history of SimGrid and in current and planned development,
+you can find out more <a href="history.html">here</a>.
+