What’s the difference between spyware and a virus?

A reader recently wrote us to say that Microsoft Windows Security Center was telling him that he had no antivirus software installed. He had finished his free trial of Microsoft Windows Live OneCare and removed it and then installed Microsoft Windows Defender, thinking it would protect his computer from viruses.


Windows Defender helps protect you from spyware, but it’s crucial that you also have antivirus software to help protect you against viruses.


What’s the difference?


·          Spyware and adware  collect information about you without appropriate notice and consent. 


·          A computer virus spreads software, usually malicious in nature, from computer to computer. 


Spyware can get installed on your computer in a number of ways.  One way is via a virus. Another way is for it to be secretly downloaded and installed with other software you’ve chosen to install. You and I both know how easy it is to skip reading all the documentation on a free program and just click “OK.” That’s often how they get you.


In short, spyware is a specific type of unwanted software that covertly collects your information. A virus is a specific way software can be covertly distributed, often by e-mail.  Both spyware and viruses can cause damage to your computer or cause you to lose important data.



Now it’s time to start protecting yourself from both.  To help protect against spyware, try Windows Defender. For viruses, consider Windows Live OneCare  or software from another antivirus provider.

About the Author
Eve Blakemore

Group Manager, Trustworthy Computing

Eve Blakemore is a Group Manager for Trustworthy Computing who delivers consumer guidance around the latest trends in security and privacy. Eve joined Microsoft in 1998 and has worked in corporate and field roles with Microsoft Learning, US Public Sector, Read more »