Before we can begin programming you'll need to install software called the Python interpreter on your computer. (You may need to ask an adult for help here.) The interpreter is a program that understands the instructions that you’ll write (or rather, type out) in the Python language. Without the interpreter, your computer won't be able to run your Python programs. We'll just refer to "the Python interpreter" as "Python" from now on.
The Python interpreter software can be downloaded from the official website of the Python programming language, http://www.python.org. You might want the help of someone else to download and install the Python software. The installation is a little different depending on if your computer’s operating system is Windows, Mac OS X, or a Linux OS such as Ubuntu. You can also find videos online of people installing the Python software on their computers at http://invpy.com/installing.