OS X now includes a built-in Firewall. The Firewall will help keep your system safe from hackers, especially on unknown networks. This video tutorial shows you how to enable the OS X application firewall and configure it for proper use.
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Its nice to find a Mac-related blog with a security section (I found you via DP).
Too many people think that the Mac and OSX/Snow Leopard are inherently totally secure but that, alas, is simply not true.
Wow, great effort! OS X is probably the most secure OS out there (after Linux). And I think that’s because inbuilt features such as firewall. Windows came out with it only recently. OS X had it all along.