Instructions: Installing Python
Installing python is easy. Python is a programming language supported by a large community of people, and with a lot of open source libraries. It is becoming a standard for scientific computing and for data analysis.
A good distribution, free even if from a for-profit company, is Anaconda.
You can install following the instructions from here: https://www.continuum.io/downloads
In order to write effectively Python code, you need an IDE (Integrated Development Environment). One IDE we will use, for sure for the introduction to Python programming, is Jupyter (previsouly, Ipython). This is a notebook style IDE and comes with the installation of Anaconda. If you need to learn how to use Jupyter, this tutorial is a good starting point.
Other more advanced choices, better for larger code development projects, are Spider (again included in the Anaconda distribution), and PyCharm from JetBrains, which you can get from here. My recommendation is Jupyter for fast prototyping and simple analysis and PyCharm (or Spider) for bigger projects.
Finally, for introducing python I will use the Iphyton notebooks from RJ Johansson, which you can download from here.
As you notice, the link sends you to github, an online free git repo. You don't know what git is? Well, it is a versioning system, which is very useful. Install it from here. You can learn more about it following one of the many online tutorials (like this one, but you can google to find the best one for you).