HTML5 Game - Canvas Coordinate system

Introduction

The canvas 2d rendering context uses a flat Cartesian coordinate system.

Its origin (0, 0) is at the top left.

Moving to the right will increase the x value.

Moving downwards will increase the y value.

Demo

<!DOCTYPE html>

<html>
  <head>
    <title>Learning the basics of canvas</title>
    <meta charset="utf-8">
    //  w  ww.jav  a 2  s.c om
    <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"></script>
    
    <script type="text/javascript">
      $(document).ready(function() {  
        let canvas = $("#myCanvas");
        let context = canvas.get(0).getContext("2d");
        
        context.fillRect(40, 40, 100, 100);
      });
    </script>
  </head>
  
  <body>
    <canvas id="myCanvas" width="500" height="500">
      Insert fallback content here
    </canvas>
  </body>
</html>