Table of Contents

    Difference Between Virus, Worm and Trojan

    Difference Between Worm and Trojan Virus

    There’s a lot of heavy technical language revolving around the realm of computer security. A lot of users aren’t clear about the differences between these terms. For instance, most people consider every malware instance to be a virus, but that’s not necessarily the case. Terminology like Trojan, worm, virus, and more are at times used interchangeably, but all of these have individual meanings.

    Keep reading to understand the core differences between either and how you can protect your device from these problems. 

    Windows Defender Security Center


    This is a specific malware type that attaches itself to any executable file or program. Much like viruses in a human, this computer virus can spread and leave infected files as it moves. As these are executable files, they can’t auto-run. Your device will only get infected when you open the malicious file. Viruses are normally spread and reproduced using email attachments and shared files.

    Virus Detection


    Quite similar to viruses, worms have the ability to replicate working copies of themselves and infect everything in their path. The major difference is that worms are self-executable files that don’t depend on manual actions or host files and they don’t need any assistance to spread. Worms infect your system using social media and other link baits.

    Trojan Horses

    This type of malware gets its name from the wooden horse used by the Greeks to infiltrate Troy. Trojan Horses are malicious software files that look legit. Once you download and install a Trojan, your system gets attacked from all fronts. Trojan Horses can force pop-up ads, delete host files, steal user data, spread viruses, and create backdoors for other malicious codes. Unlike worms, Trojans don’t self-replicate.

    Trojan Horses Detection

    How To Differentiate Between Them?

    All of these are types of malware, yet they have distinctive features. For instance, a virus can’t spread on its own, but a worm is constantly looking for new files to attack. Trojans, on the other hand, can only be triggered through manual actions like running a downloaded file or an email attachment.

    InfectionThese are spread using email attachments and/or other shared files.Worms are spread through social media and clickable link baits.Trojans are spread when you download and execute files and attachments.
    ReproductionViruses can reproduce by copying and replicating themselves.Worms can replicate themselves as well.Trojan Horses can’t self-replicate.
    TriggeringViruses can’t be triggered remotely. It can only be triggered through manual actions.Worms can be triggered remotely.Trojan Horses can be triggered remotely as well as through manual actions.
    AttacksViruses can overwrite host files and damage the programs on your computer.Worms can take control of the file and information-transport features. Some advanced worms can use ransomware, encryption, and wiper threats as well.Trojans attack your device in multiple ways. They can take over desktop/browser settings, display unnecessary pop-up ads, steal data, damage host files, and even open backdoors for other malicious software.
    SpreadViruses spread at an average rate and mostly depend on user behavior.Worms spread faster than Trojans and viruses.Trojans spread slowly compared to Worms and viruses.

    Tips On Fighting All of Them

    The first step to stay clear of malware is to use the first-in-line security tools offered by the device. To enhance security further, you can also use a cloud-based security suite. Other safer ways are to steer clear of malicious websites by using advanced firewalls, a VPN, and deploying other preventative measures.

    Here are some effective strategies to keep malware away from your device:

    1.       Update The OS Frequently – Update the device operating system as and when you’re notified. New updates include security patches, updated malware libraries, and lots of other device protection features.

    2.       Turn On The Device Firewall – Always use a firewall to prevent apps and files from unauthorized access. Windows OS offers a good firewall feature but you can always opt for a 3rd party firewall if you need advanced security and customization.

    3.       Watch The Downloads – The Internet is full of free stuff. However, be cautious of the websites you visit and the files you download as they may be infected. Running these files on your device will also install malware.

    4.       Use Browser Protection – You can get this feature with most antivirus software. Alternatively, you can look for extensions or other open-source options. Using browser protection will help you stop trackers, crypto miners, and intrusive ads.

    5.       Download An Antivirus – For added protection, we recommend that you download any antivirus of your preference. You don’t necessarily have to invest money in it as many brands like Avast and Avira offer free versions.

    Bottom Line

    While there are a lot of technical terms, knowing some of the most common words like Trojan, worms, and viruses can help you understand the differences of each. Once you know how they work their way into your computer and impact devices, you’ll find it easier to protect yourself from these malware threats.