Piwik is a source, open (GPL) web real-time analysis software. It provides detailed reports about visitors on your website like: search engines, keywords used, the language they speak, your popular pages .
Piwik is an alternative to Google Analytics, and is already used by more than 150,000 websites.
Simply copy and paste this tag on websites that wish to track and access your reports real-time analysis.
Install Piwik on Debian Squeeze:
Step1. First we need to download the latest release of Piwik from http://piwik.org/latest.zip :
Step2. Then unzip the downloaded file. This will create a “piwik” folder containing files and directories.
Step3. Go to the URL you have installed Piwik through your web browser.
If everything is loaded correctly, you should see the installation screen Piwik welcome. If there are problems, Piwik will identify and tell you how to solve it.
Step4. Now follow the directives given by piwik and all should be fine.
NOTE: When you are done configuring Piwik, you can set more restrictive rights (ie. read only) on the “piwik/config/” folder. Piwik will always write its data inside the “piwik/tmp/” folder, so only this one needs write permission.
Official website : piwik.org
Enjoy. Feel free to ask anything.