Bokeh, a Python library for interactive visualization
Bokeh, a Python library by Continuum Analytics, helps you visualize your data on the web.
Bokeh is a Python interactive visualization library for large datasets that natively uses the latest web technologies. Its goal is to provide elegant, concise construction of novel graphics in the style of Protovis/D3, while delivering high-performance interactivity over large data to thin clients.
If you're new to this stuff, you might just want to start with D3.js simply to avoid the Python setup, but if you use Python exclusively already, this might fit well in your workflow.