diff --git a/monticore-grammar/src/main/grammars/de/monticore/types/Types.md b/monticore-grammar/src/main/grammars/de/monticore/types/Types.md
index d3a733bb2b..fec008c79a 100644
--- a/monticore-grammar/src/main/grammars/de/monticore/types/Types.md
+++ b/monticore-grammar/src/main/grammars/de/monticore/types/Types.md
@@ -83,7 +83,7 @@ generic and array types,
 ## [`MCStructuralTypes`](MCStructuralTypes.mc4)
 
 This language component allows to express additional types
-that are defined by the combination of other types,
+by combining other types,
 like the union type `Foo | Bar` which is the type that is "`Foo` or `Bar`".
 As structural types are orthogonal to other kinds of types,
 `MCStructuralTypes` can be combined with any of the above
@@ -104,7 +104,10 @@ The documentation can be found in [`SIUnits`](../siunit/SIUnits.md).
 ## [`RegExType`](../regex/RegExType.mc4) 
 
 When using this language component,
-RegEx types like `R"H(a|e)llo"` become expressible.
+Subtypes of `String` defined as RegEx types like 
+`R"H(a|e)llo"`, or `R"-?[0-9]+"` `R"0x[a-f0-9]+"` 
+become expressible. This is useful to prevent e.g. security breaches by 
+malign input text.
 This is documented in [`RegEx`](../regex/RegEx.md).
 
 ## Further Information