title: understanding the display of the pixels on the screen
body: <p>I'm sorry if this is a stupid question, but I want to make sure that I'm right or not.
  suppose we have an 8x8 pixel screen and we want to represent a 2x2 square, a pixel can be black - 1 and white - 0. I would imagine this as an 8x8 matrix</p>
  <pre><code>[[0,0,0,0,0,0,0,0],      
   [0,0,0,0,0,0,0,0],      
   [0,0,0,0,0,0,0,0],      
   [0,0,0,1,1,0,0,0],      
   [0,0,0,1,1,0,0,0],    
   [0,0,0,0,0,0,0,0],       
   [0,0,0,0,0,0,0,0],     
   [0,0,0,0,0,0,0,0]]     
  </code></pre>
  <p>using this matrix, we paint over the pixels and update them (for example) every second. we also have the coordinates of the pixels representing the square : (4,4) (4,5) (5,4) (5,5) and if we want to move the square we add 1 to x part of coordinate.</p>
  <p>is it true or not?</p>