What is Computer Virus?

What is Computer Virus?

A computer virus is malicious software that infects the computer, replicates itself, and spreads to other computers.

A computer virus can be either a program or a code that can make copies of itself after being run by the user or another program, typically with some harmful intent.

Viruses are often spread without any action on the victims’ part, but they are not considered parasitic because they do not permanently attach themselves to their hosts.

A typical example of this would be Code Red and ILoveYou, which were created to cause damage to their host machines while remaining non-destructive.

A virus may also be used intentionally as part of an attack on information systems by an individual or organization against computer security known as malware (malicious software).

Types of Computer Virus

There are several types of computer viruses. The most common ones include:

Trojan Horse

A malicious program that hides within another program, such as a game or music file.

Once installed onto your computer, it will execute its code and perform tasks such as stealing personal information or making unauthorized changes to your system settings.

Computer Worms

Self-replicating programs that spread themselves from one computer to another over networks such as LANs (Local Area Networks) and WANs (Wide Area Networks).

Like other forms of malware, worms may replicate by sending copies of themselves via email attachments or network shares.

However, unlike other forms of malware that often require user interaction before infecting the system (e.g., downloading an infected file), worms propagate autonomously once they have been executed on the target machine(s).

Logic Bomb

Malicious code is embedded into an application designed to execute at a specific time or under certain conditions set by its creators.

For example, suppose you write software checks every day before going home whether there are any unassigned tickets assigned at 2 pm on Saturday afternoon.

In that case, this could be considered a logic bomb because it will trigger when all conditions are met at one given moment in time.

Causes of Computer Virus

Computer viruses are generally installed on your computer via the following methods:

  • Downloading unauthorized software, such as pirated movies or music.
  • Clicking on links to malicious websites from emails or instant messages.
  • Using infected Flash drives to store or transfer data between computers.
  • Installing counterfeit software (pirated copies of professional applications) contains malware or viruses that can infect your device and cause issues with connectivity, data loss, and more.

Symptoms of Computer Virus

Computer viruses can be mild or severe, depending on the type of virus you have. Some viruses cause severe damage to a computer, rendering it unusable until repairs are made.

Other viruses are less harmful and may only affect specific files on your machine. The virus type will determine the symptoms you experience when infected by a computer virus.

The most common symptom of a computer virus is an error message alerting you to an issue with your machine.

You might see this message pop up when you start up your PC or use other programs on your computers like browsers or office productivity software like Word or Excel.

When these errors occur, there’s a chance that they’re due to malfunctions in hardware components such as memory cards or connections between different parts inside computers themselves.

However, they could also indicate an infection by some malicious software like ransomware (which encrypts all files stored on an infected machine) or worms (which spread rapidly among connected devices).


If you’re still with me and haven’t exited your browser in a huff, we can conclude that viruses are malicious software that can infect your computer.

The virus then replicates and spreads to other computers.

These days, it’s rare for a virus to have any kind of purpose other than destruction since most people know how to protect themselves from infections and would instead not take the time out of their day to infect someone else’s computer.

But there are still some viruses that aren’t too harmful—like ones that show funny pictures on your screen or play music when you open specific programs—so don’t be afraid!

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