Google Analytics

Google Analytics takes a look at which keywords work with your Adwords and which do not. Sweet. And it’s free! And there’s all sorts of other information that you can use!

Google Analytics tells you everything you want to know about how your visitors found you and how they interact with your site. You’ll be able to focus your marketing resources on campaigns and initiatives that deliver ROI, and improve your site to convert more visitors.

Digg < GoogleAnalytics