A virus, in terms of technology, is a type of malicious software (known as malware) that, when executed, replicates itself by modifying other computer programs and inserts its own code. Primarily, it performs harmful actions, unknowingly to the user, such as stealing personal data or damaging system processes. Essentially, a computer virus interferes with the normal functioning of a computer system.


The phonetic pronunciation of the word “Virus” is /ˈvaɪrəs/.

Key Takeaways


  1. Viruses are microscopic parasites, generally much smaller than bacteria. They lack the capacity to thrive and reproduce outside of a host body.
  2. Predominantly, viruses have a reputation for being the cause of contagion. Viruses cause diverse human diseases including common cold, flu, warts, HIV/AIDS, and COVID-19.
  3. Viruses are not alive in the same way as organisms we typically classify as living. They don’t eat or grow, they only replicate – and they do so by invading and taking over cells in a living organism.



The technology term “virus” is essential because it refers to a type of malicious software that, when executed, replicates by reproducing itself or infecting other software by modifying them. The concept is crucial in the realm of cybersecurity, as understanding it helps in preventing, detecting, and removing these harmful entities.

Viruses can lead to various negative effects, such as data loss, frequent pop-up messages, slow system performance, or even unauthorized access to sensitive data. They can be spread through emails, malicious websites, or infected software downloads.

Therefore, the term “virus” has a significant role in promoting awareness and strategies to safeguard digital data and systems.


In the realm of technology, a virus, akin to its biological counterpart, is a piece of software that is designed with the specific intent to cause damage, spread, and typically go unnoticed until its actions have already begun causing issues. It works by attaching itself to clean files, and once executed- inadvertently by the user or through automatic processes within the computer’s operating system- this malicious software starts infecting other clean files, often leading to severe system malfunctions. A virus is deliberately designed to spread from host to host and has the ability to replicate itself.

It is important to note that a virus is a type of malware, but not all malware are viruses.The primary purpose of a virus is to exploit any vulnerable system and take control away from the user for various harmful or unjust activities. A virus, once active on a system, could potentially cause several undesirable effects ranging from impeding system performance to wiping out data, to even taking control of the system. Designers of these disruptive codes often use them as tools for cyber crimes, for instance, to steal sensitive user information, which includes credit card numbers, user login credentials, and just about any valuable business or personal information available.

They may also employ viruses to cause large scale damage to networks, servers, or websites, all in pursuit of their harmful intentions. Using a good antivirus software that scans, detects, prevents, and removes these viruses can be a significant safeguard against such threats.


1. ILOVEYOU Virus: Also known as the “Love Bug Virus,” the ILOVEYOU virus is a computer worm that spread through email and file sharing. The virus sent an email with the subject line “ILOVEYOU” and a virus-embedded attachment to everyone in the user’s contact list when opened. It caused approximately $10 billion in damages, impacting millions of users globally.

2. Conficker Virus: Discovered in 2008, the Conficker virus was a worm that targeted Windows operating systems, exploiting a network service vulnerability. Once a system was infected, the virus would turn off system services, disable security features, and block access to various websites. It resulted in millions of infected computers, forming a large botnet.

3. CryptoLocker Virus: Introduced in 2013, the CryptoLocker virus is an example of ransomware. Once it infected a system, it would encrypt the user’s files. The hackers behind the virus then demanded payment in exchange for the decryption key. This caused widespread disruptions and significant financial loss.

Frequently Asked Questions(FAQ)

Q1: What is a Computer Virus?

A1: A computer virus is a type of malicious software that, when executed, replicates itself by modifying other computer programs and inserting its own code. It often affects the operation of computers negatively, causing system crashes, data corruption, or loss.

Q2: How does a Computer Virus spread?

A2: A computer virus typically spreads through email attachments, downloads, or by visiting infected websites. It can also propagate through network file system, USB drives or other forms of data exchange.

Q3: How to protect your computer from Viruses?

A3: Install a reliable antivirus software, keep it updated, and perform regular scans. Keep your operating system and other software updated. Be cautious with email attachments and downloads, and avoid visiting suspicious websites.

Q4: Can a computer Virus be removed?

A4: Yes, most viruses can be removed using a good antivirus software. However, it’s important to note that some viruses can cause irreversible damage to your device or data.

Q5: What are the effects of a Computer Virus?

A5: Depending on their type, viruses can slow down your computer, delete or corrupt files, send spam, steal sensitive information, log keystrokes, or even gain complete control over your computer.

Q6: What’s the difference between a Virus and a Worm, or a Trojan?

A6: All three are types of malware. A virus attaches itself to a program and propagates when the program is run, whereas a worm operates independently and spreads across networks without help. A Trojan misrepresents itself to appear harmless, only to perform malicious tasks once inside your system.

Q7: What is the history of the Computer Virus?

A7: The first academic work on the theory of computer viruses (i.e., self-replicating programs) was done by John von Neumann in the late 1940s. The term “virus” was first used to denote a self-replicating program by Fred Cohen in his 1984 academic paper.

Q8: Can smartphones get Viruses?

A8: Yes, smartphones can get viruses, although it is less common than on computers due to their more restricted operating systems. The same principles of protection apply: only download applications from trusted sources, don’t click suspicious links, and consider using a mobile antivirus application.

Q9: Can Macs get Viruses?

A9: Yes, while Macs are traditionally seen as safer than PCs, they can still get viruses. It’s less common, largely due to the fact that the majority of viruses are targeted at Windows systems, however, the risk still exists.

Q10: What to do if you think you have a Virus?

A10: If you suspect that your computer is infected, stop using the internet immediately to prevent further damage or data theft. Update and run your antivirus software. If the virus can’t be removed, you could need to reinstall your operating system. Always seek professional advice if you are unsure.

Related Tech Terms

  • Malware
  • Antivirus software
  • Worm
  • Trojan
  • Phishing

Sources for More Information


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