// Learning Processing
  // Daniel Shiffman
  // http://www.learningprocessing.com
  
  // Example 16-6: Drawing a grid of squares
  
  // Size of each cell in the grid, ratio of window size to video size
  // 80 * 8 = 640
  // 60 * 8 = 480
  int videoScale = 8;
  
  // Number of columns and rows in our system
  int cols, rows;
  
  void setup() {
    size(640,480);
    
    // Initialize columns and rows
    cols = width/videoScale;
    rows = height/videoScale;
  }
  
  void draw() {
    
    // Begin loop for columns
    for (int i = 0; i < cols; i++) {
      // Begin loop for rows
      for (int j = 0; j < rows; j++) {
        
        // Scaling up to draw a rectangle at (x,y)
        int x = i*videoScale;
        int y = j*videoScale;
        fill(255);
        stroke(0);
        // For every column and row, a rectangle is drawn at an (x,y) location scaled and sized by videoScale.
        rect(x,y,videoScale,videoScale); 
      }
    }
  }