Highcharts

Highcharts is a JavaScript charting library written = an easy way of adding interactive charts to websites. Highcharts currently supports line, spline, area, areaspline, column, bar, pie, scatter, angular gauges, arearange, areasplinerange, columnrange, bubble, box plot, error bars, funnel, waterfall and polar chart types. Plus it is free for personal use, education, and non-profits!