CTparental is a free and open-source parental control tool used to control computer usage or internet browsing. It comes with a simple and easy-to-use web interface powered by a Lighttpd web server. The idea of CTparental tool comes from other tools such as, iptables, dnsmasq, and inguardian privoxy.
The Debian Administrator's Handbook is a fantastic resource for all users of a Debian-based distribution. Accessible to all, this book teaches the essentials to anyone who wants to become an effective and independent Debian GNU/Linux administrator.