Press 1, 2, 3, . . . ,9, 0 to see ten pictures, each consisting of 1000 lines. Use Turbo or not. Take a look at the code: Can you see why the project is called "Just changing one number value . . ."?
How the pictures are drawn: 1000 points on a curve are pairwise connected to 1000 points on another curve by lines. For beautiful advanced examples of using this technique, take a look at http://www.ams.org/publicoutreach/math-imagery/yeganeh