That "virus writers don't make viruses because there are fewer Macs than PCs" is a lie first perpetrated by Microsoft, and picked up by ignorant
Mac is based on the BSD kernel, which is a sibling of Linux. MOST SERVERS ON THE INTERNET RUN LINUX. Therefore, most computers on the internet run
the functional equivalent of what the Macs run.
The fact is this: Unless you take serious steps to lock down a PC running windows, EVERYONE has administrative rights on the machine. What this
means is that if one account on there gets a virus, the whole machine (and every account on it) is affected. That's not to mention that, even with a
locked down machine, it is still EXTREMELY LIKELY to be compromised if hooked directly to the internet, without being behind a firewall.
Macs do not work like that. By default, every account is limited, so if you catch a virus, it only affects that account. Unless you run the virus
using the "root" account, it's not going to affect the whole machine. It is an inherent difference in architecture that keeps macs from getting
anywhere near the viruses, NOT that fact that there "are less Macs".
Please note that I am not claiming that Macs don't get viruses, but that the chance to get a virus if you have a Mac is very, very much less than on
a Windows machine. And if you do happen to get a virus on the Mac, the chances of an easy cleanup are much, much greater. Usually (but not always)
just rebooting the machine, logging in as root, delete the offending files, and you are good to go. Unless, of course, it was the root account that
There is also the simple fact that most software (unless it is acting as a "server"), does not run in privileged space, but in the user space. When
you open Word, for example, EVEN ON A LIMITED ACCOUNT, on a PC running Windows, it runs in system (i.e., privileged) space. When you open a word
processor on a Linux/Mac system, in runs in user space. So, if a document is opened that has a virus on a PC, it will infect the whole machine. If
it happens on a Mac/Linux machine, it will only affect that user's account. The same with web browsers. Suppose your browser gets hijacked on a
windows machine, the entire machine will be infected. If the same happens on a Mac/Linux machine, you go in on the root account, delete the infected
files located in the user's HOME directory, and they will be good to go. Only the user was infected, not the whole machine.
Most software that connects to the internet on Mac/Linux machines runs under a separate account that gives it access to only that program. So, even
if that particular software does get a virus, it will (generally speaking) only infect that particular piece of software.
The "Macs only get less viruses because there are less of them" has been debunked so many times, by so many geeks, that is beyond debate at this
point. Remember, there is a good chance that this web site runs on Linux.
[edit on 13-6-2008 by sir_chancealot]