Adware
Software supported by adverts
Adware is essentially any software that is funded by advertising.
Some forms of adware are relatively benign, commercial programs which provide a free version which displays advertising. Others are more insidious, as there is money to be made from pushing adware onto unsuspecting users. This is generally done via 'affiliates' so that the company producing the adware itself can remain legal. Some adware may also install itself in such a manner as to become difficult to remove, hiding components and disabling removal techniques. Adware may also gather sensitive user information from a system, such as browsing habits.
A piece of software pushed by affiliates without user consent crosses the line to become a trojan. Stealing private data without consent renders an item spyware. Many products exist which aim to detect, block and remove adware - some focus only on more malicious kinds, while others can target any kind of advertising.
