Testing a shellcode

I have this piece of code to test a shellcode but I don't understand it so can anyone explain it to me?

Forget about the assembly shellcode, what I want to understand is the C code,

char shellcode[] = "...";

int main(int argc, char **argv)

{

int (*func)();

func = (int (*)()) shellcode;

(int)(*func)();

}

I mean everything, what are the empty (), please explain it as if you are explaining it to a beginner.