Decomposition.md

@@ -24,4 +24,14 @@ finding a graph partitioning where each group contains the same sum of
 weights, and the sum of the cut edges is minimal. Even if a model decomposition
 it is not bind to a graph model it is true that until now is the main approach
 
-* CartDecomposition
\ No newline at end of file
+* CartDecomposition
+
+## Fixed decomposition
+
+The decomposition is choosed and by the user and kept fixed.
+
+ 
+
+## Data Driven decomposition
+
+Data are divided across processors, It is the default decomposition before the model based decomposition is created