createCanvas(400, 200); // set the size of the canvas

  background(255) // fill the canvas with white pixels

  angleMode(DEGREES) // use degrees rather than radians for arc()

  // pick a light grey fill and bright red stroke to draw shapes with

  fill(200)         // a single value is greyscale

  stroke(200, 0, 0) // three values are red/green/blue

  strokeWeight(4)  // line weight in pixels

​

  // draw four shapes – one after another

  square(50, 50, 40) // (x, y, size)

  circle(150, 50, 40) // (x, y, diameter)

  arc(250, 50, 40, 40, 90, -90) // (x, y, w, h, start, end)

  rect(50, 120, 200, 40) // (x, y, w, h)

}

​