Hacker programs called “port scanners” rapidly scan all the ports to your computer to find an opening to your computer. Once in, these programs typically run other programs and downloads that can steal your credit card number and other information, gather data to steal your identity, damage your system, and more. This kind of unauthorized access is exactly what a firewall is designed to stop.
Another way that hackers get into your computer is through a phenomenon called “security holes.” Security holes are the unwatched “back doors,” unintentionally created as software is developed. The trouble is that hackers can get around a basic inbound firewall by exploiting security holes you didn’t even know were there. Only an outbound and OSFirewall can stop them.
As we saw above, security holes can allow hackers to get by firewalls that only have inbound protection. That means that your valuable information could then be transmitted to the hacker—unless your firewall was capable of automatically blocking unauthorized outbound communications.