What is a computer virus? Why do people create viruses?

Anyone using laptops, computers, or electronic devices shares a common fear called "viruses". These viruses cause severe damage to device data and system resources, especially on computers. So what is a computer virus? Let's join VPTS learn about common virus types and quick, effective prevention methods in the article below.

What is a computer virus?

Definition:A computer virus is a form of malicious software (malware) designed to inject itself into files or systems, then carry out harmful actions such as stealing data, damaging systems, or degrading computer performance.

As its name suggests, a computer virus operates much like a biological virus: it can spread itself from one computer to another via USB drives, emails, downloaded files, or even LAN/Internet networks.

Harmful effects of computer viruses

In reality, as Industry 4.0 technology continues to advance, this inadvertently makes computer viruses more “sophisticated”. While computer viruses previously only damaged hardware, today's viruses are capable of infiltrating systems, destroying, and stealing critical data. Additionally, computer viruses also encrypt information for ransom, causing great anxiety for users.

Taking the example of a hacker famous Vietnamese hacker – Ngo Minh Hieu, currently released on parole after serving 7 years in US federal prison, shocked the United States in 2020. Hieu used computer viruses to breach systems and steal data, personal identities, credit cards, bank accounts, etc., of American citizens. After hacking, he resold this information to cybercriminal groups. Hieu's use of computer viruses not only caused financial losses to victims, but also compromised their safety when criminal groups used data purchased from Hieu to extort victims.

Common types of viruses

With the sophistication and advancement of technology, cybercriminals also execute more "sophisticated" tactics to create millions of dangerous viruses aimed at stealing user data. Among them, some common virus types you should know include:

• Macro Virus: This type of virus commonly resides in Excel and Microsoft Word applications. The preferred habitat of a Macro Virus is document files. When you transfer these files to another computer, the virus spreads along with them.

• Web Scripting Virus: This is a type of virus that exists on website. The main activity of a Web Scripting Virus is overwriting code on a specific website, where cybercriminals will insert harmful links to computers. From there, data cookie and your personal information will be easily stolen.

• Multipartite Virus: Multipartite Virus is a type of fast-spreading virus. Not only that, this virus also infects multiple places including computer systems, files, operating system and memory.

• File-infecting Virus: A parasitic virus that typically spreads through data files with .exe or .com extensions. This virus corrupts data files and can even damage the hard drive format.

• Browser Hijacker Virus: A type of virus that alters browser settings. This means that when you click a link containing this virus, you will be redirected to an unintended browser.

• Resident Virus: This type of virus automatically resides directly in the user's computer memory. As a result, it can spread to other files while causing operating system errors whenever programs are launched.

• Boot Sector Virus: USB drives or hard drives are often where this type of Boot Sector virus appears. Therefore, be careful when sharing USB drives with anyone else.

• Polymorphic Virus: Given the sophistication of cybercriminals, Polymorphic Viruses were created to "evade" antivirus scanning software pre-installed on your computer. This type of virus is formidable because it can mutate its code each time the infected file is accessed by a user.

Attack methods of various virus types

Attack methods of viruses are increasingly sophisticated and diverse, ranging from rapid self-replication and spreading to exploiting complex security vulnerabilities. Below are the avenues through which viruses can spread to your computer:

• According to the classical method: Computer viruses spread via USB drives, hard disks, phones, etc., when users share these devices with an infected computer.

• Email-transmitted virus: Viruses often appear in files or links attached to email. When someone sends email this to you and you accidentally click the link, your computer will be infected with a virus.

• Viruses spread over the Internet: Viruses exist in files attached to certain websites. Especially when downloading applications to your computer, choose reputable websites to prevent downloading virus-infected applications.

• Routine-based virus: First, you need to understand that routine represents a module specific, also known as a "subroutine". When users trigger tasks to invoke a routine, this process sends instructions to the routine to carry out a specific request from server. Consequently, viruses in the form of routines began to emerge, altering the address parameters of random instructions to redirect toward the virus's own code. Thus, upon completion, the virus transfers control to a routine specified by its creator. The spread rate of a routine virus varies depending on the author's capabilities.

What is the nature of a virus?

The nature of a virus is malicious code attached to specific software. Each type of virus has its own function aimed at destroying or damaging your computer system. Computer viruses are also a major concern for many users because most aim to steal data and information from users to conduct extortion schemes.

How to prevent computer viruses

To minimize viruses infiltrating your computer, prepare the most fundamental ways to protect your PC with:

Use antivirus software

Currently, many reputable antivirus software options are available on the market. To make sure you choose a genuine, high-quality program, you can read user reviews and ratings for each software. Using antivirus software to alert the computer promptly upon detecting abnormal intrusions from other platforms is also an ideal way to protect users' computers from damage.

Perform system freeze

When the computer system is 'frozen', its state remains unchanged, thereby curtailing the spread of viruses. In addition, if infected, the virus is automatically eliminated upon restarting the computer.

Establish usage policies

Establishing usage policies is one of the most effective solutions for computer virus prevention. For example, critical data should always be stored elsewhere to allow easier recovery when needed. Additionally, regular virus scanning is another essential usage rule that everyone—individuals and businesses alike—must practice.

Copy and store data

Occasionally, your computer may still become infected with viruses, severely affecting critical data files or even destroying them. Therefore, you need to form the habit of backing up data to other devices or locations so that if the machine gets infected, you can still recover the data you need.

Reference:Popular computer antivirus software 

What is computer virus spreading?

Below are some common ways your computer can become infected with viruses:

Virus email

Email is one of the preferred vehicles for computer viruses everywhere. You can get infected with a computer virus via email by:

• Open an attachment. It is often named something harmless (such as Your Flight Itinerary), an executable program file (.com, .exe, .zip, .,, doc, .dot, .xls, .xlt, xlsm, .xsltm).

• Open an email with content malicious. In the era of graphics and colors rich with bells and whistles, some viruses are transported within the body of HTML of the email itself. Many email services disable HTML by default until you confirm that you trust the sender.

Instant messaging virus

Instant messaging (IM) is another medium for virus spread. Skype, Facebook Messenger, Windows Live Messenger and other IM services are inadvertently used to spread viruses to your contacts via infected links sent through chat messages.

These instant messaging and social media viruses spread rapidly because people are more likely to click a link when it is sent in a message from someone they trust, as opposed to an email from a stranger.

File-sharing virus

Peer-to-peer file sharing services such as Dropbox, SharePoint or ShareFile can also be used to spread viruses. These services sync files and folders with any computer linked to a specific account, so when someone (accidentally or otherwise) uploads a virus-infected file to a file-sharing account, that virus is downloaded to everyone else who has access to that shared folder.

Some file sharing services, such as Google Drive , scans uploaded files for viruses (although it only scans files smaller than 25MB). But most other services do not scan for viruses at all, so it is your responsibility to ensure that you are protected against any potential threats in the files you are downloading.

What are computer virus downloading programs?

Fake virus infection is one of the most common ways malware-laden software is downloaded. Scammers and cybercriminals use ads and scare tactics to convince users that a non-existent virus has been detected on their PC, urging them to download "turbo-speed" antivirus software to eliminate the threat. Instead of removing computer viruses, this rogue antivirus infects the PC with malware, often causing serious consequences for the victim's files, hard drives, and personal information.

Vulnerable unpatched software

Last but not least, one of the most common (yet frequently overlooked) ways viruses spread is unpatched software. Outdated software refers to programs and applications that have not been updated with the latest security patches from developers to fix security vulnerabilities within the software itself.

Unpatched software is a cybersecurity headache for businesses and organizations, while cybercriminals exploit vulnerabilities in outdated versions of popular programs such as Adobe Reader, Java, Microsoft Windows or Microsoft Office , ordinary people like us are also at risk of infection.

Why do people create viruses?

The most frequently asked question is:“Why do people create viruses to harm others?”In reality, the motives for creating viruses are very diverse, broadly categorized into several main groups:

1. Testing Purpose&study

• In the early days, many viruses were programmed by students or IT professionals to test programming skills and demonstrate capability.

• However, gradually these experimental programs caused unintended harm as they spread widely.

2. Sabotage Purposes

• Some individuals or organizations deliberately create viruses to delete data and disrupt systems, causing work interruptions for users or businesses.

• This is a dangerous type of virus with severe consequences.

3. Monetization purpose

• Nowadays, most viruses are created for financial profit:

• Ransomware: encrypts data, forcing victims to pay a ransom.

• Spyware/Keylogger: stealing account information, passwords, and bank cards.

• Botnet: turns computers into "zombies" to mine cryptocurrency or conduct DDoS-for-hire attacks.

4. Political or espionage purposes

• Viruses are also used in cyber warfare, where nation-states or hacker groups attack adversary infrastructure to gather intelligence or paralyze systems.

CONCLUSION

Through the article above, we can see that computer viruses are not merely disruptive code snippets, but genuine threats to data, systems, and business operations. Whether created for research, destruction, or profit, the common thread is that viruses always pose information security risks and cause severe damage to users.

To protect against these risks, every individual and business needs to equip comprehensive security solutions, use secure infrastructure, and regularly back up data. This is also why many customers trust and chooseVPTS– a reputable provider of VPS, servers, and security services, helping you grow your operations without worrying about viruses or malware.

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