Class Hierarchies(Chapter 15 of The C++ Programming Language)

[1] Use ordinary multiple inheritance to express a union of features; [2] Use multiple inheritance to separate implementation details from an interface;[3] Use a virtual base to represent something common to some, but not all, classes in a hierarchy;[4] Avoid explicit type conversion (casts); [5] Use dynamic_cast where class hierarchy navigation is unavoidable; [6] Prefer dynamic_cast over typeid;[7] Prefer private to protected ;[8] Don’t declare data members protected; [9] If a class defines operator delete(), it should have a virtual destructor;[10] Don’t call virtual functions during construction or destruction;[11] Use explicit qualification for resolution of member names sparingly and preferably use it in overriding functions;