Chart.js – Standalone Charting Library With HTML5 Canvas
It currently supports 6 chart types (line, bar, radar, pie, column and polar area) and all this comes in a standalone, <5kb package.
Colors, fonts, borders and their sizes can all be customized. Also, optionally, charts can be loaded with an animation.
As the library is built with canvas, it works on a wide set of browsers, loads fast but lacks interactivity.