A few years ago, you'd have been right if your hunch was that you probably don't need to bother with antivirus software on your iMac or MacBook. Windows was still the primary target, with Android rapidly increasing as a platform for criminals to exploit.
However, a recent report from Malwarebytes shows that you can't be complacent in 2020. It found there was an increase in Mac threats of over 400 percent in 2019, compared to the previous year.
It also found that the number of threats detected by its software running on Macs rose from an average of 4.8 in 2018 to 11 in 2019, which is almost twice as many as on Windows.
Macs are now a prime target for cybercriminals, and although macOS has built-in security, it is not so effective against adware and PUPs - potentially unwanted programs.
When you consider that Macs are expensive, and so their owners tend to be wealthier than the average PC users, they start to look like an attractive target.
Do you need virus protection on a Mac?
There are no technical reasons why Mac users cannot be exploited. The operating system might be inherently more secure than Windows, but it is worth remembering that the end-user is always the weakest link. Unfortunately, unlike a machine, you can be fooled by a phishing email that cons you out of precious login details or a scam that tricks you into installing malware.
In many ways, security software exists to save you from bad decisions - installing apps that appear to offer something for nothing, but turn out to be spyware or viruses.
So for the price of a cup of coffee each week, it makes sense to install security software and then forget all about it.
Let's take some advice from the experts. Our colleagues over at Macworld have the definitive guide to the best antivirus for Mac. It is regularly updated, and is worth checking out as some of the best Mac antivirus products are free. Right now the number one recommended product is Intego's Mac Internet Security X9 (with a free trial), with BitDefender Antivirus a close second.
Do Macs have built-in virus scanner?
No. But there are security features. Gatekeeper is one, and it verifies any downloaded app before allowing it to run. This helps to ensure that apps are safe to use, but it doesn't replace antivirus software.
If you use Safari as your web browser, then you're automatically protected from dangerous and fraudulent websites as well. However, this is not a cast-iron guarantee that malware won't get past the defences.
What type of malware can Macs get?
Mainly it's adware and 'unwanted' programs which misbehave. An example is NewTab. This redirects searches in a web browser to earn the criminals money from affiliate schemes. It usually arrives on your Mac in apps with embedded Safari extensions.
How do these apps get installed? Mainly from fake and fraudulent websites. For example, Malwarebytes found a fake package tracking website which would accept any number entered and then download a PackagesTracker app when you click the 'Track' button. Naturally, this does not track packages, or even pretend to.
Mac antivirus software is not prohibitively expensive - for 20 or so pounds or dollars, it will put your mind at rest and your valuable data in a much safer place.
You may also consider using antivirus on your Mac if for some reason you could be targeted individually - if you have access to sensitive or high-value data, for instance. If you do choose to buy Mac antivirus, take a look at the best Mac antivirus software roundup put together by our colleagues on Macworld.
What follows is the counter-argument as to why Macs don't need antivirus, but we still think it's better to be safe than sorry.
Why Macs don't need antivirus (but aren't immune)
All the evidence suggests they don't. Anecdotally, I've had an unprotected Mac connected to the web for more than 15 years, and I have never had a problem. Why this is the case is worth investigating, however.
The argument most often put forward is a simple one of market economics: because Apple's global market share is in single figures, criminals go after the bigger shoals of fish in the Windows and Android worlds.
There is something in this - virtually all current malware exists to generate cash for criminals. Crooks are not known for their application or invention, so the biggest, easiest target gets all the attention.
However, as we've seen, Mac malware is indeed increasing at a rapid rate. Yet, as a Unix-based operating system, macOS is by its very nature sandboxed. It's like having a series of fire doors - even if malware gains access to your Mac, it is unable to spread to the heart of the machine.
Macs are not unhackable, but they are more difficult to exploit than are Windows PCs. So just as a burglar could break into a house with an alarm system but will probably choose the unprotected dwelling next door, a Mac makes a less attractive target in a world in which only attractive targets tend to be attacked.
And if you are savvy and can avoid all the usual traps of opening dodgy email attachments and clicking on fake websites, then you are likely to keep your Mac free of nasty adware and PUPs.
As I've said, the latest versions of macOS - actually everything since OS X 10.8 Mountain Lion - take this even further. They include the GateKeeper function that by default prevents you from installing anything other than Apple-approved software.
Do Macs get slower over time?
Like all computers, they can slow down as you install and use more and more apps. The resources available remain the same, so you are using up storage, RAM and processing power, especially if you run a lot of apps at the same time.
If your Mac is running slow, it's unlikely to be a virus. But here are 7 tips for speeding up macOS.