|Elk Cloner was the first virus|
to affect desktop computers
I've heard this claim from many Mac users as well as from the company itself. However, it just so happens that the very first known piece of malware was written for the Mac*.
The Elk Cloner program was written by Rich Skrenta in 1982 (a year before Fred Cohen demonstrated a virus proof of concept on
Skrenta has a website with a page dedicated to Elk Cloner. If you want to know what it looked like, see the image above.
Apple plays down the malware threat to Macs and makes interesting claims such as, "A Mac isn’t susceptible to the thousands of viruses plaguing Windows." This is, perhaps, rather obvious. In the same way, a Windows PC isn't susceptible to malware that affects Macs.
The same can't be said for Macs versus Linux computers, though. There is some compatibility, which means that Linux malware can sometimes run on Macs (perhaps with a little tweaking).
Mikko Hypponen from F-Secure has presented a short documentary about the Brain virus and even interviewed the original authors, who are legitimate businessmen working from the same address as they were in 1986. You can watch this below:
* It really depends on how you define virus, malware and so on but arguably the first virus was a worm called Pervade, which was unleashed onto UNIVAC systems in 1975 by John Walker. It wasn't an internet worm, though, because 'the internet' did not exist in the way that it does today.
** Thanks to Anonymous (below) for noting my stupid mistake :)