experimente y es magnifico, cada dia me va gustando mas todo esto.
<canvas width="600" height="600"> </canvas>
<script>
var pantalla = document.querySelector("canvas");
var pincel = pantalla.getContext("2d");
pincel.fillStyle = "white"
pincel.fillRect(0,0,600,600);
pincel.fillStyle = "blue"
pincel.fillRect(0,0,200,200);
pincel.fillStyle = "red"
pincel.fillRect(0,400,200,200);
pincel.fillStyle = "red"
pincel.fillRect(400,0,200,200);
pincel.fillStyle = "blue"
pincel.fillRect(400,400,200,200);
//arly
</script>
