We will be using the IDLE software to type in our programs and run them. IDLE stands for Interactive DeveLopment Environment. The development environment is software that makes it easy to write Python programs, just like word processor software makes it easy to write books.
If your operating system is Windows XP, you should be able to run Python by clicking the Start button, then selecting Programs, Python 3.1, IDLE (Python GUI). For Windows Vista or Windows 7, just click the Windows button in the lower left corner, type "IDLE" and select "IDLE (Python GUI)".
If your operating system is Max OS X, start IDLE by opening the Finder window and click on Applications, then click Python 3.2, then click the IDLE icon.
If your operating system is Ubuntu or Linux, start IDLE by opening a terminal window and then type "
idle3" and press Enter. You may also be able to click on Applications at the top of the screen, and then select Programming, then IDLE 3.
The window that appears when you first run IDLE is called the interactive shell. A shell is a program that lets you type instructions into the computer. The Python shell lets you type Python instructions, and the shell sends these instructions to the Python interpreter to perform.