How Does Antivirus Software work?


Antivirus software keeps computers safe from cybercriminals and hackers who get a thrill out of causing problems for other people. Once this type of product is installed on your computer, you shouldn’t even notice that it is there most of the time. It is reassuring to know that this software is keeping you safe, but you may be curious about how it is actually doing this. Knowing about how antivirus products work also mean you can make more informed choices when buying this type of product.

The Basics of Antivirus Software

These days antivirus software can come with lots of additional features, but its basic job is to protect your computer from malicious software (malware). It not only means preventing viruses from taking over your machine but also other threats like worms, Trojans, and ransomware. This can be achieved in two main ways:

  • monitoring your system for any type of suspicious behavior
  • examining files on your computer to see if there are any matches to known malware on the virus directory

Detection of viruses is a key function of antivirus software, but a quality product will also be able to remove the threat and prevent malware from gaining access to your system in the first place.

How Does Antivirus Software Recognize Viruses?

Every virus has its own signature, and this is how it is possible to recognize it. The antivirus products have a virus directory where all the currently known threats are listed. This list is constantly being added to, and this is why paid antivirus software is regularly updated. Every time you open or close a file on the computer, or send one as part of an email, it is checked by the security software. It is also usual for all of your files to be scheduled to be scanned regularly. Once a file is recognized as having a signature belonging to a virus, it can be dealt with in an appropriate way.

Even if a computer virus is so new and rare that it isn’t listed in the virus directory, it can still be identified by antivirus software. This is because the system is being constantly analyzed for any suspicious behavior. If your computer begins to behave strangely, the antivirus program can usually pick this up - an example of this would be any attempt to change the code for an executable program. This constant scanning of the system is also important because some viruses have the ability to camouflage their signature so that they don’t appear as a threat.

Not All Antivirus Software is Created Equal

There are lots of different types of antivirus software to choose from, and these products can differ greatly in the amount of protection they provide. The most basic version will just perform a scan of your system to see it there are any files with suspicious looking signatures. The best free antivirus options will not only scan your system but put anything threatening into quarantine – this level of protection can be enough for people who don’t use a computer too much. The paid products have a virus directory that is constantly being updated, and they also work in ‘real time’ to prevent malware from accessing your computer.

Basic antivirus software only offers you limited protection against certain types of malware, and this is why it can be a good idea to purchase a security suite. This product comes with added protection such as:

  • Anti-spyware capabilities to protect you against programs that track your movements online or potentially even steal your identity (e.g. keylooggers)
  • Anti-phishing technology to make it harder for cybercriminals to trick you into revealing sensitive information
  • Spam filtering so that your email inbox isn’t full of junk
  • Parental control to keep your kids safe online
  • Protection against adware

The makers of antivirus products regularly add additional features to their premium subscriptions to make these options more attractive to customers. One extra function that can be very useful is backup of data in the cloud. This means that no matter what happens to your computer, your data is always going to be kept safe.


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