• Some objects are associated with a small set of values.
• And names are associated with each of the possible values.
• Suppose we are representing a piece of four part harmony.
• We want to refer to the four parts as soprano, alto, tenor and bass.
• Some programming languages provide a means for declaring types
  that represent a small number of values.
• Such types are enumeration types, enumerated types or enum types.
• First language: Pascal. Later: Modula-2, Ada, C, C++ and C#.
• Notable exception (until now): Java.