Pop-up ads, or
advertising-supported software, is any software package which
automatically renders advertisements in order to generate revenue for
its author. The advertisements may be in the user interface of the
software or on a screen presented to the user during the installation
process. The functions may be designed to analyze which Internet sites
the user visits and to present advertising pertinent to the types of
goods or services featured there. The term is sometimes used to refer to
software that displays unwanted advertisements
Adware, or advertising-supported software, displays advertising banners or pop-ups on your computer when you use your Internet Browser (Internet Explorer, Mozilla Firefox, Google Chrome or Opera). This is not necessarily a bad thing. Such advertising can fund the development of useful software, which is then distributed free (for example, Android apps, many of which are adware funded).
However, adware becomes a problem if it: