For quite some time I’ve been recommending the Macintosh for general usefulness and how it tends to have a much reduced problem with viruses and other forms of malware. Now, however, it appears that the bad software is getting more common and they are targeting the Mac more often.
While I believe the Mac can be made much more secure than a PC more easily (and with fewer inconveniences to the user as a result), my opinion has always been that the primary security feature of the Mac is that there are fewer of them and most of the bad software targets Windows. There have been some examples recently of malware targeting not only the Mac, but Linux as well.
Sophos has an article which details the history of malware on the Macintosh. It’s not pretty to think how sophisticated the bad guys are getting with how they are able to target the Mac and other platforms with the same malware. The attack vector is usually the same for all in that it tells you that you need to install some software to see a video. The malware determines which operating system you are using and tells you to download the file which works on your computer.
I’ve recommended free antivirus software for Windows for many years. My current favorite is Microsoft Security Essentials. Other free antivirus is available from Avast, AVG, and Avira. There’s also the open source ClamWin, but I don’t recommend it for most people. Until recently, the only free option on the Mac was the open source ClamXav. Again, I wouldn’t recommend it for most people. Back in November, Sophos introduced a free commercial-grade antivirus for the Mac. Like the free Windows options, it’s only available for home users for free.
Sophos is a bigger name in Europe than it is in the US. They’ve been doing antivirus solutions for many years and I trust their product. I’ll be putting it on my Macs at home and I recommend that you do the same with yours.