This is the tutorial I am looking at for Open GL.
http://fly.srk.fer.hr/~unreal/theredbook/chapter01.html

Here is the program I'm trying to get to work

Code:
#include <iostream>
#include <gl.h>

using namespace std;

int main()  {

   glClearColor(0.0, 0.0, 0.0, 0.0);
   glClear(GL_COLOR_BUFFER_BIT);
   glColor3f(1.0, 1.0, 1.0);
   glOrtho(-1.0, 1.0, -1.0, 1.0, -1.0, 1.0); 
   glBegin(GL_POLYGON);
      glVertex2f(-0.5, -0.5);
      glVertex2f(-0.5, 0.5);
      glVertex2f(0.5, 0.5);
      glVertex2f(0.5, -0.5);
   glEnd();
   glFlush();

   cin.get();
}
But I get a list of errors that stem, seemingly, from the same source. One such example is the following.

" undefined reference to 'glClearColor@16' "

I just started to look into OpenGL recently, and some help is greatly appreciated. And if anyone knows a better tutorial, other than cprogramming.com, then please do tell.