nThe initialization list causes the base class
constructor to be
invoked with the correct arguments!
nThe order of the arguments for the base class is very important. They must be listed in the same order as the base class constructor expects.
n If we had not
included the base class constructor in the initialization list of the derived class, then the
default base class constructor
would be invoked.
nIf no default base class constructor exists, then a compile error results.