Cytoscape.js is a graph theory library for analysis and visualisation.
flowchart.js draws simple SVG flow chart diagrams from textual representation of the diagram. Also diagrams can be with color view too.
Vega is a visualization grammar, a declarative format for creating and saving interactive visualization designs.
With Vega you can describe data visualizations in a JSON format, and generate interactive views using either HTML5 Canvas or SVG.
Two.js is a two-dimensional drawing api geared towards modern web browsers. It is renderer agnostic enabling the same api to draw in multiple contexts:
Paper.js is an open source vector graphics scripting framework that runs on top of the HTML5 Canvas.
It offers a clean Scene Graph / Document Object Model and a lot of powerful functionality to create and work with vector graphics and bezier curves, all neatly wrapped up in a well designed, consistent and clean programming interface.
Yako.js is a tiny DOM-less graph library, build for fast front end and server side rendering in CommonJs pattern. This library is intend to generate light weight and simple SVG graphs, and is more performable compare to highcharts / flot / c3 / d3 when front end matters.
twgl.js library's sole purpose is to make using the WebGL API less verbose.
Chartinator is a jQuery plugin that transforms data from HTML tables, Google Sheets and js arrays into charts using Google Charts.
A tutorial about how to create a gorgeous, interactive animated pie chart by using HTML5 canvas element, CSS3 and jQuery.