When used as a function return type, the void keyword specifies that the function does not return a value. When used for a function's parameter list, void specifies that the function takes no parameters. When used in the declaration of a pointer, void specifies that the pointer is "universal."
If a pointer's type is void *, the pointer can point to any variable that is not declared with the const or volatile keyword. A void pointer cannot be dereferenced unless it is cast to another type. A void pointer can be converted into any other type of data pointer.
A void pointer can point to a function, but not to a class member in C++.
You cannot declare a variable of type void.