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What is a Computer Virus?
A virus in a computer is harmful software that can damage or disrupt how your computer functions.
To explain what viruses do, they attach to files and hide malicious code, ready to cause damage when activated. The virus stays inactive until a person runs or opens the infected file, which causes it to spread and infect other parts of the computer.
Unlike worms, which can spread on their own, a virus needs a person to take action, like opening an email attachment, downloading an unsafe file, or clicking on a dangerous link. Once activated, viruses can slow down your computer, delete or damage files, and cause other serious problems.
Key Takeaways
- A PC virus is a harmful software that attaches to files or programs. It stays inactive until opened, then spreads, causing slowdowns, file loss, or serious damage.
- The role of a virus in cybersecurity is significant because hackers create them for cybercrime, sabotage, or fame.
- Viruses spread through email attachments, downloads, USB drives, and outdated software.
- Common types of computer viruses include boot sector viruses, macro viruses, file infector viruses, polymorphic viruses, resident viruses, overwrite viruses, and browser hijackers.
- When learning about computer virus safety, key steps include using antivirus software, updating regularly, avoiding suspicious emails and websites, using strong passwords, and browsing securely.
What Causes a Computer Virus
Knowing about computer virus motivations can help you understand what causes a virus:
- Cybercrime: Many hackers use viruses to commit cybercrimes, such as stealing important data, such as personal details, banking information, or passwords. This stolen data can be sold or used to make money.
- Sabotage: To explain computer virus motivations, some are made to cause deliberate damage or disruption. This can be due to political reasons, competition between companies, or even state-sponsored attacks aimed at critical infrastructure.
- Ego and fame: Some hackers want to show off their skills and gain recognition. They create viruses to get attention, prove their abilities, or become famous in the hacking community.
Viruses often spread by taking advantage of weaknesses in software. In a cybersecurity context, hackers search for these flaws to insert their harmful code. They can then spread the virus through infected email attachments, risky downloads, or compromised websites, making it easier to target and harm users.
How Do Computer Viruses Spread?
If you define viruses in computer contexts, it becomes clear how they take advantage of everyday actions and software flaws.
Understanding how computer viruses spread is key to staying safe:
Many viruses are hidden in email attachments or files that people download. When someone opens these attachments or downloads the files, the virus is activated.
Viruses can also be passed through USB drives or external hard drives. If someone connects an infected device to their computer, the virus can transfer and start spreading.
Downloading files from unsafe websites or file-sharing networks can expose users to viruses that are hidden in the files.
Hackers take advantage of old software and browsers with security gaps. These vulnerabilities make it easier for viruses to infect and damage a computer.
5 Symptoms of a Computer Virus
There are several symptoms of computer virus infections:
Types of Computer Viruses
Here are seven common types of computer viruses and how they work:
This virus attacks the master boot record of your computer, making it hard to start up or even making the system unbootable. It usually spreads through infected USB drives or other removable media.
Found in files like Word or Excel documents that use macros, this virus runs when the file is opened. It can spread to other documents and may corrupt or steal data.
This type attaches itself to executable files and activates when you run the program. It can damage or delete files and spread to other software on your system.
This virus constantly changes its code to avoid being detected by antivirus software, making it hard to find and remove.
It hides in your computer’s memory and continues to infect files even if the original virus file is deleted. It can cause ongoing issues.
This virus deletes the content of a file by overwriting it with its own code. Once a file is infected, the original data cannot be recovered.
This virus changes your web browser settings, like your homepage or search engine, and redirects you to unwanted or harmful websites, often causing annoying ads and pop-ups.
What is a Computer Worm?
A computer worm is a type of malware that spreads on its own, without any help from you.
To explain the differences between computer viruses and worms: a virus needs user action, while worms move automatically across networks. Once a worm infects your device, it can slow down your system, steal data, or even let hackers in through hidden backdoors.
So, what is a computer worm exactly? It’s a self-spreading, sneaky piece of malware.
Famous Computer Viruses Examples
Several well-known computer virus examples have become known and taught us important lessons about cybersecurity.
- One famous virus is Melissa, which appeared in 1999. It provides an excellent example of what viruses do, because it caused email servers to crash and disrupted many businesses. The virus spread through infected Word documents sent by email.
- Another well-known virus is ILOVEYOU, which appeared in 2000. It spread quickly through email, pretending to be a love letter. Millions of computers were infected, causing billions of dollars in damage by overwriting important files.
- Finally, the Mydoom virus, released in 2004, stands out in computer viruses examples for how fast it spread and the damage it caused. It targeted Microsoft Windows, slowing down the Internet and causing significant problems, showing the need for strong antivirus software.
How Can You Prevent Viruses and Malicious Codes?
Here are 6 tips on how you can prevent viruses and malicious code from infecting your computer:
Practice these virus basics, and you should be perfectly safe.
The Bottom Line
Understanding the computer virus definition helps you realize that PC viruses are dangerous and can cause a lot of problems. Knowing about computer virus threats and how they work, spotting the warning signs, and following simple prevention tips can help you keep your devices safe.
Remember: employ virus basics by staying alert, keeping your software updated, and avoiding risky clicks or downloads.
