Chapter 15 Unified Threat Management for FortiOS 5.0 : Security Profiles overview : Content inspection and filtering : FortiGuard Web Filtering
  
FortiGuard Web Filtering
The web is the most popular part of the Internet and, as a consequence, virtually every computer connected to the Internet is able to communicate using port 80, HTTP. Botnet communications take advantage of this open port and use it to communicate with infected computers. FortiGuard Web Filtering can help stop infections from malware sites and help prevent communication if an infection occurs.