Free, open source D3, InfoViz, Processing.js, and Recline.js bring dynamic, interactive -- and jaw-dropping -- data-driven graphics to the Web browser
Where HTML5 meets big data
If you need straightforward charts, manipulated in a straightforward fashion, then you should be pleased with InfoVis. Just package your data into JSON and feed it to the right chart object -- you have your graph. On the other hand, if you're looking for a library that will take you beyond data visualization -- that can produce abstract graphic designs or even pure animations -- then look no further than Processing.js.
If, however, you're more interested in your data than in its visualization -- that is, if your main objective is to explore your data rather than create animated and interactive charts and diagrams with it, and you only need a handful of basic, solid graph types -- then consider Recline.js. It provides tools for getting your data into its library from numerous sources, and it provides routines for querying and analyzing the data once it's there.