This second synchronization is made by sending HTTPS queries through Tor to several websites and deducing a correct time from their answers. You can see the list of websites that Tails can connect to in *[[!tails_gitweb config/chroot_local-includes/etc/default/htpdate.pools desc="/etc/default/htpdate.pools"]]*.
<p>If a software is not included in Tails, but is included in Debian, you can use the [[Additional Software|doc/persistent_storage/configure#additional_software]] feature of the Persistent Storage to install it automatically every time you start Tails.</p>
