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We{{Chicago are going to practice writing andPython runningWorkshop/Setup/Windows Python scripts.}}
===Start your text editor===
# Launch the Notepad++ text editor. See the [[Chicago Python Workshop 1/Friday/Windows_text_editor|Windows text editor setup]] instructions for the steps to do this.
# Start a new, blank text file.
===Write and save a short Python script===
# Add the following line to your new text file:
<pre>
print "Hello World!"
</pre>
# Saving the script
## Click either the Save button or going to <code>File > Save</code>
## Then, navigate to your Desktop folder, which will be under <code>C:\Documents and Settings\<username></code> or <code>C:\Users\<username></code>.
## Once you've double clicked on the Desktop folder, then click the new folder icon. Then name it <code>python</code>. This is where we will keep all our python code and projects, so that it's easy to find.
## Then click through the python folder you just created, and save the file as <code>hello.py</code> in this python directory. The <code>.py</code> extension indicates that this file contains Python code.
===Run the script===
# Start a new command prompt. See the [[Chicago Python Workshop 1/Friday/Windows terminal navigation|terminal navigation on Windows]] instructions for the steps to do this. Recall that a terminal prompt will look like <code>C:\</code> and a Python prompt will look like <code>>>></code>. Make sure you are at a terminal prompt and not a Python prompt; if you are at a Python prompt, you can type <code>exit()</code> on a line by itself and then hit enter to exit Python and return to a terminal prompt.
# Navigate to your python directory, which is in your desktop directory, from a command prompt, using the <code>dir</code> and <code>cd</code> commands. See the [[Chicago Python Workshop 1/Friday/Windows terminal navigation|terminal navigation on Windows]] instructions for a refresher on using these commands. Don't hesitate to get help from a staff member on this step if you need it -- it's a new way of navigating your computer, so it may be unintuitive at first!
# Once you are in your python directory, you'll see <code>hello.py</code> in the output of <code>dir</code>.
# Type
<pre>
python hello.py
</pre>
and hit enter. Doing this will cause Python to execute the contents of that script -- it should print "Hello World!" to the screen. What you've done here is run the Python application with an argument -- the name of a file, in this case "hello.py". Python knows that when you give it a file name as an argument, it should execute the contents of the provided file. You get the same result as if you typed
<pre>
print "Hello World!"
</pre>
at a Python prompt and hit enter.
===Success===
You created and ran your first Python script!
* When you run the <code>python</code> command by itself, you start a Python prompt. You can execute Python code interactively at that prompt.
* When you run the <code>python</code> command with a file name as an argument, Python executes the Python code in that file.
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