By Default, if you use the standard Javascript Tracking Tag, Piwik will only track visitors with Javascript Enabled in their web browser. You can however configure Piwik to also track users with Javascript disabled: to do so, edit the Piwik Tracking Tag <noscript> and change:

<noscript><p><img src="http://piwik-server.com/piwik.php?idsite=1" style="border:0" alt="" /></p></noscript>

Replace with the following:

<noscript><p><img src="http://piwik-server.com/piwik.php?idsite=1&rec=1" style="border:0" alt="" /></p></noscript>

After making this change and adding &rec=1, visitors with disabled Javascript will execute the noscript and will load the piwik.php image and will have their traffic recorded in Piwik.

Note: the most famous bots will still be ignored with this technique. To force Piwik to track all bots, add the parameter &bots=1 to the tracking URL, eg:

<noscript><p><img src="http://piwik-server.com/piwik.php?idsite=1&rec=1&bots=1" style="border:0" alt="" /></p></noscript>