Your computer can fall victim to many destructive events: power surges, coffee spills, a failed hard drive, or worse. But your computer is also susceptible to a digital invader called a virus.
A virus is a program that attaches itself to another program and spreads from one file to another, causing varying degrees of damage. You may not even notice some viruses, but malicious ones can erase your data files, corrupt your applications, cause your computer to crash, and, in certain cases, render your hard drive completely useless. For more on computer viruses, see Understanding Computer Viruses.
Avoiding Viruses
Viruses can be transmitted via e-mail attachments, so monitor your in-box for suspicious messages. If you don't know the person who sent you a message, don't open any attachment that came with it.
You can't get a virus from simply opening an e-mail message, but your e-mail client may be configured to automatically open attachments, in which case you should disable that feature. Be especially aware of attachments with the suffixes .exe or .com. If you activate this type of virus, it can attack executable files, overwrite code, and cause irrevocable damage.
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