Many many switchers coming from the Windows world are always concerned about whether or not they need a firewall or antivirus software for their Mac. The short answer: maybe, it's a personal choice.
Having a firewall is always a necessity to protect your computer and network from hackers who could steal data or harm your machines. Luckily Mac OSX has it's own built-in firewall that can be activated in the Sharing pref pane in System Preferences.
Now when it comes to antivirus software it gets trickier and there isn't as much agreement. Here are the normal pros and cons...
Pros:
If you use the machine in a mixed network antivirus software will help stop you from further infecting the network. While your Mac can't be infected by a Windows virus, it can pass it on.
Even though there is not a virus for Mac OSX that doesn't mean there will never be one. Having antivirus software installed makes you proactive in your protection.
Most users see no performance decrease or issues when running antivirus software.
Cons:
There has never been a virus or spyware released for Mac OSX to date.
It eats up resources on some machines
In certain situations it could cause stability issues or kernel panics
As you can see there are good reasons on both sides so in the end you need to make up your mind on which your most comfortable with.
If you decide to add an antivirus program to your computer here are some that are available for OSX:
Mac Specs: 1.67 Ghz 17" PB w/1 GB Ram; 400 MHz PM G4, 366Mhz iBook Firewire, Nano 4GB Black
I'd tend to disagree with the "Most users see no performance decrease or issues when running antivirus software." I know that for the time I had Virex running on my computer, I noticed about a 10% slowdown at times, and I'm running the top of the line Powerbook. I agree with the rest of your thread though, this really needed to be posted.
While your Mac can't be infected by a Windows virus, it can pass it on.
I suggest changing "it" to "you." The Macintosh can't transmit the virus, at least not in the way that an infected PC can. Only the operator could (accidentally or unknowingly...or deliberately) send the virus on.
Also, in addition to resource or performance issues, antivirus software might affect stability. Especially those AV programs that install kernel extensions (kexts) which can increase the likelihood of kernel panics or other issues on some machines...a Very Bad Thing.
Other minor gripes
I suggest changing "it" to "you." The Macintosh can't transmit the virus, at least not in the way that an infected PC can. Only the operator could (accidentally or unknowingly...or deliberately) send the virus on.
Also, in addition to resource or performance issues, antivirus software might affect stability. Especially those AV programs that install kernel extensions (kexts) which can increase the likelihood of kernel panics or other issues on some machines...a Very Bad Thing.
I suppose if you want to break it down to the definition of specific wording, then yes I could change it . However since this is just a general FAQ for newbies, I don't really know if it's necessary to break it down into a linguistic battle of semantics .
As for your other comment, you are correct, that may also be an issue for some users although certainly not widespread. Thanks for adding to the FAQ.
having the os x firewall on or off did not make a difference when it came to running shieldsup on www.grc.com. both passed the trustealth test with flying colours. so should i have it on or off?
Mac Specs: MacBook 2.4Ghz Black 4GB;iPod Touch 8GB;iPod mini 4GB silver;Logitech MX1000;
i have norton i didn't notice a slow down,
and i use my pen drive with pcs alot,
i am glad to see that it scans it every time, so i am not spreading any viruse
having the os x firewall on or off did not make a difference when it came to running shieldsup on www.grc.com. both passed the trustealth test with flying colours. so should i have it on or off?
Are you running your Mac after a router (wired or wireless)? If so, the test is actually testing the router's firewall, not your Mac.
I'd recommend leaving it on if you ever user your Mac on other networks since you can't be sure of their security.
Great thread... When i made the switch, antivirus was one of my first concerns/questions. I'm still getting used to the fact that i can surf the net as free as it was intended to be.
Are you running your Mac after a router (wired or wireless)? If so, the test is actually testing the router's firewall, not your Mac.
I'd recommend leaving it on if you ever user your Mac on other networks since you can't be sure of their security.
i am running my ibook after a wireless router (net gear wgr614v5). i have a desktop running winxp on this network with the free edition of sygate firewall. i have windows firewall turned off.
Yes, your wireless router has a built in firewall (all routers do) which is why the results are always the same since it's actually probing that firewall and not your Mac. If you really wanted to see your Mac's results you'd need to connect it directly to the DSL or Cable modem.
My understanding was to always have some sort of protection for your computer.
I mean, im running two Windows 2003 Servers, three Windows XP Pro Clients, one Apple iBook and one Apple Quad 2.5Ghz PowerPC (I've ordered this, should arrive within 3 weeks) at home.
On a Microsoft Platform, an Anti Virus program is a MUST.
On an Apple Platform, an Anti Virus program is not esstiential?
I’ve got a good security system (see below):
Internet --> Router* --> Windows 2003 (Running Microsoft ISA 2004, this is advanced firewall program) --> Switch* --> Windows 2003 (Running Active Directory, File Server) --> Switch* --> XP Clients & OSX Clients.
*Switch = 3Com
At this moment I don't have any Antivirus programs for the Apple machines, I do have for the Windows machines, they all run Norton Antivirus Corp (latest version with latest definitions). In which I can control all XP clients from one machine, I will like to do this with Mac’s as well.
For the purpose of continuity, I'm guess I would purchase Norton Antivirus Mac edition. Am I making the right move, should I consider another antivirus application or should I bother at all?
As I'm a University student, software developer (Mac & Windows), graphics designer and network engineer, security is a number one priority for me.
Any further advice and information would be an extremely beneficial.
. However since this is just a general FAQ for newbies, I don't really know if it's necessary to break it down into a linguistic battle of semantics 
.
