Does C have classes?

No, C has no classes per se, only C++ (which started out as "C with classes" back then...). But you can use the standard C library in C++ code, even if it is often not considered good practice (where C++ has its own, higher level constructs, e.g. cout vs printf).

You can sort of emulate the behaviour of classes, inheritance and virtual functions in C too, but it's not worth the pain.

You should probably buy/get your ex classmate a C programming book :-)

No, C doesn't have classes. That said, there are ways of simulating object-oriented programming in C - a quick Google search should yield some useful results.