ZoneAlarm Pro 5 Firewall + Privacy Protection Intrusion Blocking systematically identifies hackers and blocks access attempts. Stealth Mode automatically makes your computer invisible to anyone on the Internet. ID Lock prevents your personal data from leaving your computer without your approval. Ad Blocking automatically stops pop-up ads so you can surf in peace. Automatic Program Configuration provides safety and simplicity by automatically configuring programs. Automatically decides whether to allow or deny Internet access to individual programs.