jCanvaScript is a javascript library that provides you methods to manage with the content of a HTML5 canvas element easily. It runs on any platform (including iPhone, iPad, Android) that supports canvas and JavaScript. To add support for canvas in Internet Explorer you can use ExCanvas.
Features
  • Fully Object Oriented
  • Provides access to the canvas context
  • Provides mouse-events to all objects
  • Provides keyboard-events to all objects
  • Provides drag'n'drop
  • Easy methods to manage objects
  • Provides easy objects animation
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You can familiarize with library possibilities on the following example:
Example
Growing circles
Code of example
var interval_1=0;
function startShow()
{
	var r = Math.floor(Math.random() * (254)),
		g = Math.floor(Math.random() * (254)),
		b = Math.floor(Math.random() * (254)),
		x = Math.floor(Math.random() * (439)),
		y = Math.floor(Math.random() * (554)),
		color = "rgba("+r+", "+g+", "+b+", 0.5)",
		filled = true,
		radius = 1;
	jc.circle(x, y, radius, color, filled)
		.animate({radius:100, opacity:0}, 1500, function(){
			this.del();
		});
}

function onload_1()
{
	jc.start(idCanvas, true);
	interval_1 = setInterval(startShow, 200);
}

function start_1(idCanvas)
{
	if(interval_1)return;
	onload_1();
}

function stop_1(idCanvas)
{
	clearInterval(interval_1);
	interval_1 = 0;
	jc.clear(idCanvas);
}
View of example