Spyware on the other hand is more covert and usually undetected in your system until you run an anti spyware program. Spyware is used exactly to spy on you. In relatively mild cases, spyware is used to track your Internet browsing habits so that the spyware can report your preferences to build a marketing profile. This means that as you go about your Internet business, you are under surveillance and your basic right to privacy is impinged upon.
In severe cases though, certain spyware better labeled as malware, are used for criminal purposes and can steal keywords and other sensitive information based on your computer and Internet usage.
For instance, malware can take note of your keystrokes or take note of your credit card number and other vital information that can be used to steal your identity and generally put your security at risk.It is said that 9 out 10 computers are infected with spyware and to make sure that you are not part of statistical majority, you need run an adware and spyware cleaner to detect unwanted security and privacy breach within your system.