var canvas = document.getElementById("canvas")
var ctx = canvas.getContext("2d")


ctx.fillStyle = 'rgb(200,0,0)';
ctx.fillRect(10, 10, 55, 50);


var fps = 30; 
function draw() { 
  setTimeout(function() {
    requestAnimationFrame(draw); 
    // Drawing code goes here 

  }, 1000 / fps); 
}