Raphael vs GraphicsJS

Because Raphael supports rendering VML + SVG, it is one of the few drawing libraries that is backwards compatible with older browsers that do not support canvas.

Several built-in animations (such as ways of easing) are provided for you out of the box, but Raphael also allows cubic beziers for more complicated easing functions. Any drawing object property can be modified making it similar to css animations in jQuery.

Everything that is drawn in Raphael is an object which means it is easy to manipulate any part of the rendered image after it is processed. It uses an event handler system for user inputs which makes it easy to learn for JavaScript developers used to event based libraries.

An interactive chart demo.

This style of handling objects makes Raphael a good fit for rendering interactive diagrams and charts that can also interact with other parts of the page.

gRaphael is a Raphael extension to help you easily create graphs and charts.

Not only Bezier curves but also any lines, shapes, arcs, etc. out-of-the-box.

Clear and concise API with chaining support.

Rapid drawing. Only what is necessary is drawn.

No need to use embarrassing in-browser transformations.

IE6+.

With z-index.

Multiline text support, text measurement, wrap, indent, spacing, align, etc.

All browser events are dispatched in the same way in virtual DOM structure also.