WinPython (http://winpython.github.io/) is a free, open-source Python distribution that's maintained by the community. It is designed for scientists and includes many packages such as NumPy, SciPy, Matplotlib, and Jupyter. It also includes Spyder as an IDE. It is free and portable. You can put WinPython into any directory, or even into a USB flash drive, and at the same time maintain multiple copies and versions of it on your system. It only works on Microsoft Windows, and its command-line tool is the WinPython Package Manager (WPPM).