Regardless of the type of the site that you manage (personal blog, blog for business, online shop),visitor stats and marketing reports are essential. These reports lets you know which pages are the most important, visitor trends, which pages are weak, or, in other words, the pages with highest bounce rate and exit rates, which are the main sources of traffic, or keywords that bring you the highest traffic, or quality traffic, from search engines.
What is Google Analytics?
Undoubtedly, the best free tool for website statistics analysis and reports is Google Analytics. This is the most used web analytics tool on the market. There are other free tools such as StatCounter or awstats, but Google Analytics is by far the best choice, both because it offers a wealth of information about visits on your site, and second, offers a good integration with Google AdWords, Google AdSense
With Google Analytics you have the ability to define objectives (goals) and to track the conversion rate, creating custom reports, define custom variables to analyze in detail the behavior of certain categories of visitors (ordinary visitors, email subscribers, customers), creation and analysis of events (events) and more.