Well.... C++ was designed specifically to be an object-oriented language. That's the main difference between C and C++. You don't get classes in C, although you can make a pretty good job of simulating them with structs and function pointers. There are some things that are harder though, like encapsulation. In C++ you can have private and protected class members, whereas in standard C I think you're limited to public variables. I think you can still achieve things like polymorphism with virtual functions, but I'm not really sure. I haven't done much object-oriented programming.