How to pass a keyword from URL but keep it hidden? (Adwords)

Question

I'd essentially like to know the keyword that takes a user to my site, but then hide it from the user. So...in my ads I could set up the URL as domain.com?keyword=KW, and then store the keyword in a PHP variable so that I can use it in emails/SMS messages to myself. I don't really want it shown in the URL though as it looks kind of messy.

Is there any way to actually achieve this?

Thanks!

Answer 1

Just do a redirect after the user gets to your site:

if(isset($_GET['keyword'])){
   //do whatever function you need to do with the keyword data
   $keyword = $_GET['keyword'];
   //redirect
   header("Location: /");
}

Obviously the location should be where you want to send the user. The "/" will put him at the page/root of where he was.