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Piwik aims to be an open source alternative to Google Analytics, and is already used on more than 150,000 websites.

Piwik is a PHP MySQL software program that you download and install on your own webserver. At the end of the five minute installation process you will be given a JavaScript code. Simply copy and paste this tag on websites you wish to track (or use an existing plugin to do it automatically for you) and access your analytics reports in real time.

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