Google analytics is a free service from google which can be used for optimising performance of webistes by publishers. Its advance and easy to use method lets benefit a site alot. By using google analytics you can find which users are coming to your site and what they look for when they are visiting your site. By using google analytics you can find easily how many users are visiting you site and how they look for information on your site, which gives you an important edge over controling the traffic of your site.
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