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Timeline of the Worst Computer Viruses in History

Timeline of the Worst Computer Viruses in History

Reading time: 3 minutes
Viruses are unfortunately a risk that all computer users face. It may have happened to you before: You receive an email with an attachment, you download it, and now, your computer has slowed to a crawl or you see a fraudulent charge on your credit card. Computer viruses can cause millions — or even billions — of dollars in economic damage.
The HP research team set out to create a timeline of the most damaging and famous computer viruses in history.
Timeline of the Worst Computer Viruses in History

What Computer Viruses Caused the Most Monetary Damage?

It’s hard to pinpoint just how much monetary damage a computer virus can cause. Many cases of infection go unreported, and the extent of damage caused can be hard to quantify. However, these are generally regarded to be some of the most devastating computer viruses in history in today’s dollars.
  1. MyDoom (2004): MyDoom is one of the most infamous and worst viruses in history. During its peak, it was responsible for nearly 25% of all emails sent. It caused about $55,000,000,000 in damage.
  2. Klez (2001): This computer virus ended up infecting 7.2% of computers in the world. It was able to spoof an email sender’s name to trick people into opening an email. It ended up being responsible for $48,000,000,000 worth of damage.
  3. Sobig (2003): This devastating virus wreaked havoc among businesses around the world and resulted in $44,400,000,000 in damage.
  4. ILOVEYOU (2000): Despite the sweet name, this was one of the worst viruses in history. It disguised itself as a fake love letter and ended up causing an estimated $24,000,000,000 worth of damage.
  5. Code Red (2000): This virus eventually infiltrated the official website of the White House, requiring them to change their IP address. This viruses caused $3,700,000,000 in damage.

What Is a Computer Virus?

A computer virus is defined as a computer program that can modify other programs on the computer once it is executed. It typically requires a host program so that the virus can insert its own code, which executes when the infected program is opened. Viruses can infect both desktop computers and laptop computers. The term “computer virus” is also commonly used to describe other types of malware, like worms, ransomware, spyware, and Trojan horses.

How to Protect Yourself From Computer Viruses

It’s easier than you think to fall victim to a computer virus. In order to protect yourself from harmful viruses, you should do the following:
  • Buy legitimate software and make sure that it’s up to date. Many viruses come in through back doors in bootleg software or software that is not up to date.
  • Don’t click on links or attachments from email addresses that you don’t recognize. This is a common way for viruses to infect computers.
  • Leave websites that redirect you to another website immediately.
  • Use reputable antivirus software and a popup blocker. These will keep you safe from some of the most common computer viruses.
  • Regularly back up your data just in case your computer is infected with a virus.

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