sketch.js

function setup() {
	createCanvas(640, 480);

	// use anti-aliasing
	smooth();

	// no stroke on my shapes
	noStroke();
	
	/*
	  use upper left corner
	  not the center
	*/
	ellipseMode( CORNER );
}

/*
  draw a circle with random color
  but what if there were a way to make it easier to
  increase the x-value without doing the math ourselves?
  */

function draw() {
	// set the background color every loop
	background( 247, 250, 248 );

	// fill with RGB
	fill( 46,213,101 );
	ellipse( 20, 20, 20, 20 );

	// fill with HEX
	fill( "#864DE1" );
	ellipse( 50, 20, 20, 20 );

	// fill with color variable
	fill( 242,123,158 );
	ellipse( 80, 20, 20, 20 );

	// fill with random color (but every loop)
	fill( random(0,255), random(0,255), random(0,255) );
	ellipse( 110, 20, 20, 20 );
}