Mac hints and tips
Turn on the firewall
The Apple Mac is much more secure than some other types of computer, such as Windows PCs for example, but it is not completely impervious to attack from hackers and malware and you should always be on your guard.
OS X has a firewall built in to the operating system, which is a utility that protects your computer by only allowing certain incoming and outgoing network traffic and blocking unauthorised activity. But is it turned on? How can you tell?
You should immediately check its status because if it is turned off it will leave your computer open to hackers who could access personal information stored on the hard disk drive. It is worth thinking about the next time you use your MacBook in a public place with a Wi-Fi connection. Click the Apple logo in the top left corner of the screen and then select System Preferences from the menu. Click Sharing (Security in OS X 10.5) in the Internet and Network section and then Firewall. Turn it on if it is not currently active.
Enable firewall logging
Is OS X's firewall working? Are you sure? Is anyone trying to hack into your computer? How can you tell?
You can answer all of these questions by turning on firewall logging and then by examining the log that is created at regular intervals.
Click the Apple logo in the top left corner of the screen and then select System Preferences.
Click Sharing (Security in OS X 10.5) and then Firewall. Click the Advanced button and then tick Enable Firewall Logging.
After using your computer for a while, return here and click the Open Log button to see what events the firewall has detected.
Enable firewall stealth mode
OS X's built in firewall prevents unauthorised people and their programs (hackers in other words), from accessing your computer without your knowledge. To make it even harder for them to break into your Mac you can enable the firewall's stealth mode. This makes your computer invisible to other computers on the network or internet by limiting the responses to any network traffic it may receive. Only authorised network traffic is allowed through and unauthorised traffic elicits no response from your Mac so a hacker can't even tell it is connected.
Click the Apple logo in the top left corner of the screen and then select System Preferences. Click Sharing (Security in OS X 10.5) and then Firewall. Click the Advanced button and then tick Enable Stealth Mode. You'll be much safer now.