ZoneAlarm is the best personal firewall. Like most firewalls, ZoneAlarm alerts the user to any hacking attempts the PC. Significantly, it alerts on outbound attempts, when an unrecognized program seeks to access the webt. The firewall that Microsoft includes in Windows XP lacks outbound protection, highlighting the need for firewall protection beyond what it offers. In ZoneAlarm, access requested by any program can be allowed or denied. The user can easily specify preferred access privileges for different programs either as each seeks access for the first time, or later. The free version of ZoneAlarm is generally recognized as a good firewall, and is a very popular. Zonelab's business model is to continue to improve the free basic model while offering upgrades with more features for a low price.