Style #14
==============================

Constraints:

- The larger problem is decomposed into 'abstract things' that make
  sense for the problem domain

- Each abstract thing is described by what operations the things of
  that abstraction can eventually do

- Concrete things are then bound, somehow, to the abstractions; mechanisms
  for doing that vary

- The rest of the application uses the things not by what they are but
  by they do in abstract

Possible names:

- Abstract things
- Abstract data types