What Is Malware?

Malware is a combination of the words malicious + software. Malware is any software designed to cause damage to your computer or files, or that causes your computer to act in a harmful way. Malware can:

  • Impair device performance. Malware can slow down your computer significantly. Sometimes malware hijacks a portion of your computing power to run programs for the cybercriminal’s network. Your computer can be a part of a global chain of computers spreading even more malware.
  • Mine your computer for personal information. Malware can search your computer files and send them to a cybercriminal.
  • Install ransomware. Ransomware encrypts your documents and files and locks you out of them. Once your data is locked up, you have the choice to either pay a “ransom” or lose your data forever.
  • Install spyware. Spyware records what you do on your computer. Spyware can log sites you visit, email you write, even your keystrokes.
  • Install adware. Adware can redirect you to sales sites and take over the typical advertising displayed as you surf the Internet.

How does malware get on your computer?

Every computer connected to the Internet is constantly under attack. Your anti-virus software monitors these attacks and stops them (see the Anti-virus and updates module for more information). Sadly, human error is often responsible for successful attacks. Stop and think before clicking on links that may be sent to you by a scammer.

  • Be careful of links. Scammers use links they include in messages to direct you to dangerous websites that can install viruses on your computer.
  • Leave websites when your anti-virus software alerts you. If your anti-virus software alerts you that you are on a dangerous site, close your browser and leave!
  • Never click on or install a “.exe” file. The “.exe” stands for executable, meaning it is a file designed to make changes to your computer. Scammers will attach .exe files to spam email and direct you to open the attachment.
  • Don’t insert unknown USB drives into your computer. Cybercriminals leave USB drives (jump drives, thumb drives) laying around for the unsuspecting to pick up. Sometimes a scammer will offer a free USB drive with free music or a cool video when, in reality, it is loaded with malware that is dangerous to your device.
  • Apply security updates promptly. Software updates patch security holes. Don’t use outdated software (Windows 7 and Internet Explorer are two) and update software when required.