How to display a text generated by a shell script called by Apache?

I created a virtual host for a website located at the URL: www.google.com following this tutorial: http://ift.tt/1o9tAC9.

Now, I would like to display a message like " Hello google" generated by a shell script. And the shell script have to be call by Apache on each access request.

I tried to do this: Run a shell script with an html button but when I click on the button that downloads the php file...

Do you have an idea to do this?

Thank you!