Python 2.7 or Python 3.x?
Python 2.7 is the legacy version of Python. The 2.x versions are no longer being updated with major releases. There are differences between the 2.x and 3.x. If interested in these differences, wiki.python.org goes over these in-depth.
If you are just starting off, it is recommended that you start with Python 3.x. Then if you are interested, to start learning the differences between the two. Any example code on this site will be in Python 3.x.
What is an IDE and which one should I use?
IDE stands for Integrated Development Environment and combines features such as editing, interactive testing, debugging, and introspection features. There are many IDEs for Python, some are better than others depending on how you plan to use Python. Here are a few of them that are good for research and data science applications:
Some individuals prefer a notepad or notebook environment. In that case, here are a few good ones:
Python for Data Science recommends the Spyder IDE with the Anaconda distribution package provided by Continuum Analytics, this also includes Jupyter Notebook which is an excellent notebook environment. The Spyder IDE is a nice environment that is similar to R studio (for those that are coming from R, or plan on learning R at some other time). It comes with many libraries that will be need to use Python for data science.
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