What is spyware?
Spyware is software that secretly monitors and collects information.
Spyware can be used legally. Certain companies install it on their employees’ computers to monitor sensitive activities (in which case, it ought to be included in their contracts). It is also included in some parental control programs, which can work in a similar fashion to keep a watchful eye out for cyberbullying.
What it is after
In most cases, however, spyware is used to steal credit card details or passwords for banking websites and serial numbers.
How to block spyware
Avira Free Antivirus protects its users from spyware.