Adware is simply software that displays popup ads or other ad related screens in your web browser or on your desktop. It arrives on your pc without your consent it has no easy way to uninstall or intentionally reinstalls if you remove parts of it, changes your pc and browser settings without your consent, [...]

First off, one of the most common spyware programs that people get is called about:blank. You will know when you have this as your IE browser will begin pointing to about:blank no matter what you do.