Macs were more secure because there were fewer of them, therefore not worth the effort to attack. However they are now much more common and the hackers are now targeting them. Also because they were not often attacked their security systems have not improved on Macs to the same level as PC's.
So you should still use anti virus software with a Mac.
As I said before the greatest risk by far is spam and phishing, Macs are equally subject to attack as PC's, and as Mac user can be complacent, perhaps more so.
Desperately sad story of the assisted suicide of a grieving mother


So many of us now use the internet with very little knowledge of what we are revealing and to whom. However, there is a risk in all types of communication - letters go astray, phone calls can be overheard, etc. I wouldn't say anything on a site like this that I wouldn't say in any other public place.
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