How to run C program on Mac OS X using Terminal?

Question

I am new to C. Here is my \"Hello,world!\" program.

#include 

int main(void)    
{
  printf(\"Hello, world!\\n\");
  return 0;
}

Answer 1

A "C-program" is not supposed to be run. It is meant to be compiled into an "executable" program which then can be run from your terminal. You need a compiler for that.

Oh, and the answer to your last question ("Why?") is that the file you are trying to execute doesn't have the executable rights set (which a compiler usually does automatically with the binary, which let's infer that you were trying to run the source code as a script, hence the hint at compiling.)