Google Analytics is absolutely free! We're very pleased to be able to offer this web analytics solution for no charge, allowing anyone with a website to track conversion data, analyze the flow of visitors through their site, and identify elements of their site that could be changed to improve visitor retention.
This free version is limited to 5 million pageviews a month - however, users with an active Google AdWords account are given unlimited pageview tracking. In addition, Google Analytics is completely integrated into the AdWords front-end and with your AdWords campaign, making it easy to track your AdWords ROI.
按：GG这也是在扶植自己的用户 -- 网站站长们，起步阶段提供免费服务，等用户能挣到钱了再收费，非常好，非常好。