Proper Type as C++ Class

• Class objects are responsible for their own data
• keep data in non-public area of class (protected or private)
• control access to data through public methods
• Class objects are responsible for their own behavior
• documented behavior in public methods
• keep implemention in conformance with interface
• Class objects are responsible for their own existence
• class has appropriate constructors and destructor
• assignment operator and copy constructor are appropriately implemented (if they exist)