Google Analytics is a free web analytics tool offering detailed visitor statistics. The tool can be used to track all the usual site activities: visits, page views, pages per visit, bounce rates and average time on site etc. But it can also be used to specifically track Adsense traffic therefore helping webmasters to optimize Adwords adverts based on where visitors come from, time on site, click path and geographic location. Modeled on Urchin analytics tool Google Analytics was first rolled out in late 2005.