extra info for other languages

cpp/instances/main.cpp

@@ -3,6 +3,7 @@
 
 int main() {
   // create a new car and store it in the variable 'a'
+  // in contrast to java, c++ does not need initialization with the 'new' keyword here.
   car a;
   // set some data for that car
   a.manufacturer = "Benz";