A computer virus, much like a flu virus, is designed to spread from host to host and has the ability to replicate itself. Similarly, in the same way that flu viruses cannot reproduce without a host cell, computer viruses cannot reproduce and spread without programming such as a file or document.

In more technical terms, a computer virus is a type of malicious code or program written to alter the way a computer operates and is designed to spread from one computer to another. A virus operates by inserting or attaching itself to a legitimate program or document that supports macros in order to execute its code. In the process, a virus has the potential to cause unexpected or damaging effects, such as harming the system software by corrupting or destroying data.

What are the signs of a computer virus?

A computer virus attack can produce a variety of symptoms. Here are some of them:

  • Frequent pop-up windows. Pop-ups might encourage you to visit unusual sites. Or they might prod you to download antivirus or other software programs.
  • Changes to your homepage. Your usual homepage may change to another website, for instance. Plus, you may be unable to reset it.
  • Mass emails being sent from your email account. A criminal may take control of your account or send emails in your name from another infected computer.
  • Frequent crashes. A virus can inflict major damage on your hard drive. This may cause your device to freeze or crash. It may also prevent your device from coming back on.
  • Unusually slow computer performance. A sudden change of processing speed could signal that your computer has a virus.
  • Unknown programs that start up when you turn on your computer. You may become aware of the unfamiliar program when you start your computer. Or you might notice it by checking your computer’s list of active applications.
  • Unusual activities like password changes. This could prevent you from logging into your computer.

How to help protect against computer viruses?

How can you help protect your devices against computer viruses? Here are some of the things you can do to help keep your computer safe.

 

  • Use a trusted antivirus product and keep it updated with the latest virus definitions. 
  • Avoid clicking on any pop-up advertisements.
  • Always scan your email attachments before opening them.
  • Always scan the files that you download using file sharing programs.