Python is a programming language. It is considered one of the easier computer languages to learn and is frequently taught first, due to its simplicity. Pythonpath is an environment variable and is used to assign names to values. It is used during the development stages and is set up early on to affect the way certain processes will act on your computer.
You can easily find out if it is already installed on your computer by opening a command prompt window. From there, type python.exe. If you get an error message, you do not have it installed.