ECharts is a comprehensive charting library offering a painless way of adding interactive charts to your products.
ECharts currently supports line, column, scatter, pie, radar, candlestick, chord, gauge, funnel, map and force-directed chart types, many of these can be combined in one chart.
MetricsGraphics.js is a library optimized for visualizing and laying out time-series data. It provides a simple way to produce common types of graphics in a principled, consistent and responsive way.
The library currently supports line charts, scatterplots and histograms as well as features like rug plots and basic linear regression.