Adware includes programs that show end users advertisements, often banners, independently of user activity. This type of software is often installed on victim machines from remote sites without the user's knowledge or consent.

Many free programs available on the Internet include adware. Adware will continue to function even if the program that it comes with is closed or deleted.

Adware is usually not dangerous, but it is a nuisance and wastes time and system resources. In addition, any software that is installed and launched on a computer without the consent of the user represents a potential threat.