void* is used in C to interact with the raw bytes. In some sense, the raw bytes are the only type in C. You can try to maintain a distinction between a struct RECT{int width; int height;} and a struct POINT{int x; int y;}, but it's perhaps more appropriate to think of that as documentation for the programmer than as an actual type system. As long as your code has poorly-behaved neighbors, the types offer no guarantees.