At any given point your computer is at risk of encountering hundreds of damaging viruses. Although no computer virus is a walk in the park, there are a particular few over that over the years have caused significant damage. Here is a list of the top ten most destructive computer viruses.

Stuxnet (2009-2010) – This was the first virus that caused damage in the real world as opposed to virtual world. Stuxnet caused physical problems such as damaging machinery at a uranium enrichment facility in Natanz. Simply put, the virus affected large ‘washing machine like’ industrial systems that were used to enrich uranium. The virus caused them to spin out of control and ultimately self-destruct.

Conficker Virus (2009) – This virus created one of the biggest botnet army’s that was responsible for stealing private information and because of its size it was difficult to stop. A group of experts got together purely because they wanted to stop this virus, which infected millions of users in its prime. There still remains much confusion as to what the Conficker Virus was actually meant to accomplish. Many experts have analyzed the virus and have yet to come to a conclusion on its purpose. The virus still infects a large amount of computers.

Agent.btz (2008) – This virus was spread through infected flash drives that installed malware to steal private information. This caused the Pentagon to ban all thumb drives, and agent.btz was thought to have been the creation of foreign spies, however has never been confirmed.

Zeus (2007) – This has become one of the top tools for criminals who are looking to steal personal information. It obtains passwords, addresses, date of birth, and social security numbers which release a plethora of information. This virus is still a threat today.

PoisonIvy (2005) – PoisonIvy is a remote access Trojan that is able to secretly control an infected computer from a different location. Once the virus has been installed, the criminal can control the computer, manipulating content and accessing the computer’s speaker and webcam to record audio and video.

MyDoom (2004) – This was the fastest spreading worm we have seen yet. The virus would overload the computer with information from multiple systems and was spread through infected emails that appeared to have bounced. Once the email was opened, the malware downloaded itself and accessed the email’s address book and began infecting the users’ friends and family.

Fizzer (2003) – Fizzer was the first worm created for a financial gain. Although not as fast as some other worms, Fizzer established enough harm that Microsoft offered $250,000 in exchange for information that would lead to the creators capture.

Slammer (2003) – Slammer was an internet worm that disrupted services, both private and public. It transmitted data over the internet and attacked a few key services, bringing them to a complete stop. Some of those services were Bank of America ATM’s, 911 emergency response system located in Washington and a nuclear plant in Ohio.

Code Red (2001) – Although this worm may seem rather insignificant in this day and age, at the time of its creation it caused a great disturbance. This worm used a flaw in Microsoft Internet Information Server to disfigure or take down some websites. This virus was responsible for taking down, which caused all other government agencies to temporarily remove their websites.

Love Letter / I LOVE YOU (2000) – This virus was spread through malicious emails that featured the subject ‘I Love You.’ This spread rapidly as people were expecting to open an email from a surprise admirer however in reality they released malicious software onto their computer upon opening. Once the malware was on the computer in overwrote image files and became the first socially engineered computer virus.