SciPy. Image: SciPy. NumPy (see above) is so popular that several libraries are based on it, including SciPy. Like its inspiration, SciPy is also a free, and open-source library.

This was exhilarating news, but none of the giddy headlines mentioned that the image would have been impossible without open-source software. The image was created using Matplotlib, a Python ...

Python, like R, is an open-source language, so it is free for anyone to use. Unlike R, though, it is a fully fledged, general-purpose language and an integral part of digital life.