+/** \defgroup SD_API SimDag
+ \brief Programming environment for DAG applications
+
+ SimDag provides some functionnalities to simulate parallel task scheduling
+ with DAGs models (Direct Acyclic Graphs).
+ The old versions of SimGrid were based on DAGs. But the DAG part (named SG)
+ was removed in SimGrid 3 because the new kernel (\ref SURF_API) was implemented. \ref SURF_API
+ was much faster and more flexible than SG and did not use DAGs.
+ SimDag is a new implementation of DAGs handling and it is built on top of \ref SURF_API.
+
+ \section SD_who Who should use this (and who shouldn't)
+
+ You should use this programming environment of the SimGrid suite if you want
+ to study algorithms and heuristics with DAGs of parallel tasks.
+ If you don't need to use DAGs for your simulation, have a look at the
+ \ref MSG_API programming environment.
+ If you want to study an existing MPI program, have a look at the
+ \ref SMPI_API one.
+ If none of those programming environments fits your needs, you may
+ consider implementing your own directly on top of \ref SURF_API (but you
+ probably want to contact us before).
+*/
+
+/** \defgroup SMPI_API SMPI
+ \brief Programming environment for the simulation of MPI applications
+*/
+
+
