diff --git a/LDDsimulation/README.md b/LDDsimulation/README.md
index 680e6d0b0945bbac6c09914fb91ab1b99dc51961..e1f87cf01f4d5bafdf20287b1e43ed3a71b4d1ed 100644
--- a/LDDsimulation/README.md
+++ b/LDDsimulation/README.md
@@ -4,5 +4,23 @@ This folder contains the actual LDD simulation code. To facilitate development,
 we give a briefe description of the files.
 
 ## `LDDsimulation.py`
+If you want to read the code, this is where you should
+start.
+This file defines the core and soul of the LDD simulation code.
+It defines the class `LDDsimulation` that contains methods to setup the
+simulation and run it. Each usecase file in `../Usecases` essentially
+sets up an instance of this class and defines
+all parameters needed by the `LDDsimulation.set_parameters(kwrgs**)` function
+which gets called 
 
-##
+## `domainPatch.py`
+
+## `boundary_and_interface.py`
+
+## `solutionFile.py`
+
+## `domainSubstructuring.py`
+
+##  `functions.py`
+
+## `helpers.py`