The Piwik report “Pages > Outlinks” shows the list of external URLs that were clicked by your visitors from your website pages. Piwik will track as an “outlink” all clicks on URLs that are not the same domain as the website being tracked. For example, if your visitor click on a link to “piwik.org” on your website “example.org”, this will be counted as an outlink in the report. For each outlink, Piwik will report the number of clicks, and the number of unique clicks. Unique clicks are the number of unique visitors that clicked to a given domain ; for example, if the same visitor clicked 3 times on the same outlink, it will be reported as 3 clicks and 1 unique click. Note that Piwik is not able to track Javascript of flash links. Only HTML links are tracked, eg.

<a href='http://linkedin.com'>LinkedIn Profile</a>

If you wish to not track clicks on your subdomains as outlinks, for example if your website is “example.org/” and you don’t want to track outlinks to “news.example.org”, you can use the Javascript function setDomains(). Read more in the documentation.

Learn more about Click Tracking in general in the Javascript tagging Guide.