How Does Antivirus Software Work to Protect Your Private Data?

Antivirus software gets sold to protect your online security, but how it works may surprise you.
We receive compensation from the products and services mentioned in this story, but the opinions are the author's own. Compensation may impact where offers appear. We have not included all available products or offers. Learn more about how we make money and our editorial policies.

A good antivirus program protects against malicious code from installing and running on your computer, mobile devices, routers, and even internet-connected backup storage devices. In the case of application whitelisting, good antivirus software can even catch new threats before they have the opportunity to germinate in a new host.

With the rise of ransomware globally, a good cybersecurity product has become essential to everyday internet use. Choosing the right antivirus software for you varies heavily on what aspects you find important: cost, device coverage, device compatibility, features, and functionality are all considerations when choosing antivirus.

Keep reading to find out more about how antivirus works and narrow down your choices to the right software for you.

Featured antivirus products

Best for Best overall antivirus software All-in-one software Comprehensive security Best value
Starting price $29.00/yr (first year only) $35.99/first yr $29.99/yr (first year only) $3.19/mo (billed annually)
Features Zero-day scans, anti-phishing, ransomware protection, password manager, ad blocker Antivirus protection, VPN, password manager, security for multiple devices Antivirus, malware, ransomware, and hacking protection, Cloud backup, password manager Antivirus protection, VPN, private search engine, data leak alerts
Learn more Get TotalAV Get Aura Get Norton360 Antivirus Get Surfshark Antivirus
In this article
How does antivirus software work?
What is antivirus software?
Do I need antivirus software?
Is antivirus the same as anti-malware?
How to choose antivirus software
How much does antivirus software cost?
Free vs. paid antivirus
Bottom line

How does antivirus software work?

Antivirus software works in different ways. It can scan programs and files when they enter your device and compare them with well-known computer viruses, worms, and Trojans. When it finds these malicious viruses, it can delete them or quarantine them in a protected section until you decide whether you want to remove them.

There are three types of detection methods antivirus software uses to look for potential threats.

  • Behavior-based detection: Behavior-based detection looks at the intention of an object. The behavior gets analyzed for suspicious or abnormal actions. Anything that the antivirus software deems as unauthorized actions indicates malicious intent.
  • Heuristic-based detection: This type of antivirus detection looks for previously unknown viruses. These are the malware objects that have not gotten added to virus definition files. It scans software to determine the purpose of the files present. If the antivirus finds a threat, it flags it as suspicious.
  • Signature-based detection: Signature-based detection establishes a unique identifier for a known security threat. It flags it for future reference and identification. It looks for various patterns of programming code. That pattern is the signature, and if it gets discovered by the antivirus program again, it will flag the file as being infected.

What is a false positive?

Because antivirus software is designed to keep out unauthorized users, sometimes it can mislabel a file. It may show that a file or program is malware when it is a secure file. If your antivirus program flags something as suspicious, it means there was an action or behavior that looked threatening.

If this happens to you, try to run a quick internet search to see whether the software has issues. You can also check your antivirus program for updates, or run the disk cleanup utility that comes with the antivirus software.

Every antivirus program has a way to whitelist a file or software. Whitelisting means it is approved by your antivirus software, Your specific software will have instructions on how to whitelist a file or program.

What is antivirus software?

Antivirus software gets made to fight computer viruses. It is designed to look for potential threats and remove them once detected. Essentially, antivirus software’s job is to keep your device healthy.

The antivirus software can be one program or a set of programs that flags anything it deems as suspicious. One antivirus software program may differ from the next, but they are all meant to keep your device free from malicious threats.

Do I need antivirus software?

You need antivirus software to keep your device secure. Because malware threats are more advanced and more numerous than ever, anyone can be vulnerable to hackers getting your most private information.

Some operating systems have gotten attacked more than others. It could be the popularity of these systems. Either way, the device you use may help determine how far you want to go with your antivirus options.

Do Windows 10 computers need antivirus software?

If you have a Windows 10 computer, you are a definite target for potential cyberattacks.

There are more Microsoft Windows computers in use than any other kind. More than 76% of the world’s computers run a version of Windows and these devices are hit with 350,000 new viruses and malware threats every day. With any Windows device, antivirus protection is necessary.

Is Windows Defender good enough?

Microsoft's Windows Defender comes with a firewall and antivirus, and it's a good start to protecting your computer. But you may want third-party antivirus protection to go with it. Find out why in our Windows Defender guide.

Do Macs need antivirus software?

Macs do not appear to be as big a target for internet hackers as Windows-based machines. Part of that may be due to their lower market share, but they also include two features to prevent viral threats.

Their anti-malware program is called XProtect, and it inspects every app for possible trouble. Macs also have the Gatekeeper program to keep intruders from using software not designed by a certified developer.

Even if you use a Mac, you still need antivirus software because these devices are gaining in popularity. That makes them a bigger target for internet hackers.

Do Android devices need antivirus software?

If you have an Android device, you may feel more secure. Many people don’t realize mobile devices can get hacked.

You may feel safer using your mobile device because you use apps downloaded from the Google Play store. It scans the apps for malware before it approves them for the Google Play Store, but Android users can get apps from third-party vendors and install them from their websites. These apps can come to the user infected with malware.

For security, it is recommended that you install an antivirus program for your Android device.

Do iOS devices need antivirus software?

iOS devices may be the exception to the rule of needing antivirus software.

When you have an iOS device, every app you download and install on your phone must come from the Apple App Store. These apps get scanned for potential malware before they are allowed into the store.

Your iOS device also isolates every app so a virus cannot spread to another device. If you have an iOS device, you are most likely safe not using antivirus software.

Do Chromebooks need antivirus software?

Chromebooks can get viruses, but they have not gained the popularity that Windows machines have, so with 2% of the market share, they are not a big target for attacks.

Chromebooks also uses built-in security features, such as its “sandbox” system. This feature keeps each app and web page separate from the rest of the computer. If malicious files get in, they get isolated from the rest of the computer.

Is free antivirus software good?

Free antivirus products, like Avast Free Antivirus or AVG AntiVirus Free, are a good start. But paid antivirus programs may offer more features to help you stay safe, including real-time scanning and protection against hackers.

Is antivirus the same as anti-malware?

You may hear people mention the terms anti-malware and antivirus interchangeably, but they are not the same thing.

Antivirus refers to the software program that was designed to prevent viruses from infecting a device. A virus is a program that continues to replicate itself and uses malicious code to attack other programs or files, eventually taking them over.

Malware is an umbrella term that covers any kind of harmful software, including adware, spyware, and ransomware. In short, a virus can be malware, but not all malware are considered viruses.

How does an antivirus prevent malware?

Antivirus software uses signature, heuristic, and behavior-based detection methods to prevent malware. These methods use different approaches to prevent malware from infecting your computer.

If you have signature-based detection software, you need to keep your software updated. Otherwise, it won’t notice the new forms of malware.

The heuristic-based method finds malware by looking for similar tendencies or patterns. If a file’s coding has been noticed by the software previously, it catches the malware trying to infect your device.

Behavior-based antivirus software protects against new and unknown malware. It looks for threats based on intentions, which can catch viruses that other methods might miss.

Can an antivirus prevent ransomware?

Antivirus software can detect ransomware if it is in the software’s database. Therefore, antivirus may prevent some types of ransomware, but it may also miss some. It also cannot stop ransomware once it has located your crucial files and holds them hostage. Using the best antivirus software will give you the most protection against ransomware.

Can antivirus software prevent hackers?

One of the reasons to get antivirus software is to prevent computer hackers from gaining access to your device. The program identifies the threats to let you take action to stop them from causing harm to your network.

Antivirus software may prevent you from downloading malicious software to your computer. It may also delete suspicious emails that could have viral attachments included.

A few of the specific antivirus software programs that work hard to prevent hackers from intruding are Bitdefender, Webroot, and Norton.

Bitdefender gives you an option of not allowing apps to track your data. That offers future protection against hackers using your search history. You also get the bonus of frequent updates with your subscription. That helps contain more hacking attempts because the software will recognize more malware varieties.

Webroot is a top choice for Mac users. The software offers phishing detection and fast virus scanning. It will also label suspicious links while you are online.

Norton includes identity theft protection. It also offers webcam protection and a password manager. All of these help keep your device secure against hackers.

How to choose antivirus software

When you look for quality antivirus software, you want to consider what the package offers. Some programs allow you to choose the items you want most while not paying for what you don’t need. There are basic components of all antivirus software that are non-negotiable to keep you protected.

  1. Scanning: You want your antivirus software to allow manual scans. If you want to run a scan for any reason, you should be able to check for potential threats at any time. You should also be able to turn off a scan if you notice suspicious lag time on your device.
  2. Detection: All antivirus software should detect malware. That is the No. 1 priority of the program. Check or ask about the detection rates of the software before you purchase it.
  3. Budget pricing: When you decide on the antivirus software you want, you need to know if it meets your budget. You should know what you are paying for with the product. Is it worth the price? If budget is not a concern, you still want to know what gets included in the plan. There may be another option with the same features that costs less.
  4. Detection methods: Aside from detection rates, check on the methods the software uses to find the virus. You may want one of the three detection methods we mentioned or a combination of them. Some software offers behavior, heuristic, and signature-based detection methods all in one program.
  5. Speed: Using antivirus software will slow down your computer. There are tests that can show how much it will change the speed of your device and reveal the different programs that have varying speed performances.

How much does antivirus software cost?

There are a lot of different antivirus products on the market with a myriad of price points.

Many companies are interested in giving you a special discount your first year to get you protected and using their services. The key really is finding a product that works for what you want, how many devices you have, and your price point.

When looking for a product that works for you, it’s best to view both the product’s site and independent reviews to get a well-rounded opinion. As a jumping-off point, below are reviews of five of the most popular antivirus products on the market along with a table of their current 2023 price points.

5 antivirus products compared

Antivirus plan Price Number of protected devices
AVG Internet Security $59.98/first yr 10
Bitdefender Total Security $44.99/first yr 10
Kaspersky Standard $34.99/first yr 10
Malwarebytes Premium $79.99/first yr 5
Norton 360 Deluxe $49.99/first yr 5
*Prices as of 1/27/2023.

Free vs. paid antivirus

Everything is expensive now. As inflation continues ravaging bank accounts, paying for a cybersecurity product may seem like an excessive expense.

If you’re a PC user, Windows Defender is a pretty good product for everyday use. It does have its pitfalls, especially if you use a browser that isn’t Microsoft Edge or accidentally find yourself on a phishing website. As far as defending against malicious content, however, it’s a great zero-cost option if you simply cannot fit another thing into your budget.

MAC users have XProtect and Malware Removal Tool (MRT) built into their machines. While not 100% perfect, they're lauded as highly effective.

If you still feel you need an extra layer of security, most antivirus products do offer their own version of free software. There are advantages and disadvantages to each one.

The biggest advantage is that you have some kind of protection. The biggest disadvantage is the lack of advanced features. Some standard features of most free antivirus software are listed below.

  • Protection from all forms of malware including ransomware and spyware
  • PC tune-up tools
  • Device scans
  • Malware removal tools
  • Some website and phishing protection
  • Network protection

While many products offer basic security through their free software, viruses evolve fairly quickly and learn how to maneuver around these programs.

With a paid service, you’re likely to get additional features that will enhance your protection.

  • Email monitoring and filtering
  • VPNs
  • Phishing and spam monitoring and filtering
  • Application whitelisting technology
  • Ad blockers
  • Customer service and support
  • Multi-device coverage

There’s a popular saying in the tech space: if you aren’t paying for the product then you are the product. There’s always a risk, from free antivirus to phone apps, of businesses harvesting your data and selling it to pay for the services.

Remember, there are real people working on this software, they need revenue to pay their bills and buy groceries, too.



What does antivirus software do?

Essentially, antivirus software stops a virus from infecting your device. The malicious code that makes up malware (the modern term for a virus) can do anything from locking down and holding hostage your files to crashing your entire system rendering it useless.


Does antivirus remove viruses?

Yes, antivirus software can remove the virus or place it in quarantine for you. You can choose which option you want to use.


How can antivirus protect your device?

Antivirus software scans your files, emails, and internet searches for security threats. It protects your device from viruses that can crash your machine or steal your data.


Can I install an antivirus if I have a virus?

Yes, if the virus has not damaged your computer system files or the operating system, you can install an antivirus program if you have a virus.

Bottom line

How does antivirus software work to keep your device and data secure? By running virus scans and being in the background checking for abnormal activity, antivirus gives you an edge on malware security.

You always want to get your antivirus software from reputable sources. If you find antivirus software online, read the reviews carefully before buying. Going with a trusted brand can give you peace of mind and ensure you are getting a quality product.

Getting antivirus software is strongly encouraged due to the number of viruses created every day. Because hackers show no signs of slowing down their attempts to breach your data, you shouldn’t become complacent about keeping them out of it. See our review for more on choosing the best antivirus software.

No Fuss, Real-Time Online and Mobile Protection
Editorial Rating
Learn More
On TotalAV's website
Antivirus Software
First year discount on paid plans
  • Real-time protection from viruses, malware, and online threats
  • Blocks tracking cookies and ads, proactively monitors for data breaches, and option to schedule smart scans
  • 100% compatible with Windows, Mac, Android, and iOS operating systems on up to 3 devices
  • Lacks firewall protection

Author Details
Patti Croft is a seasoned writer specializing in technology, with three years of experience. With a B.S. in Computer Science and a background as a technical analyst and security specialist, she covers a range of topics like data security and parental control software.
Mary is a seasoned cybersecurity writer with over seven years of experience. With a B.S. in Liberal Arts from Clarion University and an M.F.A. in Creative Writing from Point Park University, she educates audiences on scams, antivirus software, and more. Her passion lies in educating audiences on helpful ways to protect their data.