Sorry, but you are 100% wrong. The only reason the Macs SEEM to be more 'secure' is that nobody bothers to attack them because the used base is so small.
And as Nuntndun pointed one when you have direct assecc to the computer in question nothing is safe. BTW the code he posted will delete EVERYTHING on a Linux box, BUT you have to have Root access to do it.
The WORST security flaw with any computer is the operator.
Edited by Amigatec, February 19, 2012 - 05:58 PM.