I have a simple questions if anyone can help. Here they are: 1) Can someone explain what a abstract data types are and what abstact base class are. If there is such a thing, what is a abstract function? What is the difference between a abstract class and a normal class which I think is called a concrete class? 2) Why is it you can''t do void function(int a[][9]) {} main() { int a[10][9]; function(a); } you have to do it like this void function(int a[][9]) {} main() { int a[10][9]; function(a); } but you can do this void function(int *) {} main() { int a[10]; function(a); } 3)What''s the difference between private and protected data types? Thank you all for your help in advance. Braves

The (protected) keyword specifies that those members are accessible only from member functions and friends of the class and its derived classes. The (private) keyword specifies that those members are accessible only from member functions and friends of the class. This applies to all members declared up to the next access specifier or the end of the class. Hope that helps.

-Jer

It's not reverse engineering, unless you get caught.