Chapter 2 – Downloading and Installing Python 17Downloading and Installing Python
Before we can begin programming, you’ll need to install software called the Python interpreter.
(You may need to ask an adult for help here.) The interpreter is a program that understands the
instructions that you’ll write in the Python language. Without the interpreter, your computer won't
understand these instructions. (We'll refer to “the Python interpreter” as “Python” from now on.)
Because we’ll be writing our programs in the Python language we need to download Python from
the official website of the Python programming language, http://www.python.org. The installation
is a little different depending on if your computer’s operating system is Windows, OS X, or a
Linux distribution such as Ubuntu. You can also find videos of people installing the Python
software online at http://invpy.com/installing.
Important Note! Be sure to install Python 3, and not Python 2. The programs in this book use
Python 3, and you’ll get errors if you try to run them with Python 2. It is so important, I am
adding a cartoon penguin telling you to install Python 3 so that you do not miss this message:
Figure 2-1. “Be sure to install Python 3, not Python 2!”, says the incongruous penguin.Windows Instructions
There is a list of links on the left side of the web page at http://www.python.org. Click on the
Download link to go to the download page, then look for the file called Python 3.3.0 Windows
Installer (“Windows binary — does not include source”) and click on its link to download Python
for Windows. (If there is a newer version than Python 3.3.0, you can download that one.)
Double-click on the python-3.3.0.msi file that you’ve just downloaded to start the Python
installer. (If it doesn’t start, try right-clicking the file and choosing Install.) Once the installer
starts up, click the Next button and accept the choices in the installer as you go. There’s no need
to make any changes. When the installer is finished, click Finish.