Added style #9

09-kinds-of-things/README.md

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+Style #9
+==============================
+
+Constraints:
+
+- The larger problem is decomposed into types of 'things' that make
+  sense for the problem domain
+
+- Each type of thing is described by what operations the things of
+  that type can eventually do
+
+- Concrete things are then bound, somehow, to the types; mechanisms
+  for doing that vary
+
+- The rest of the application uses the things not by what they are but
+  by their types
+
+Possible names:
+
+- Types of things
+- Abstract data types