Spyware: what is spyware and what does it do?

Most spyware can be broken up into two major groups: adware and malware. The majority of spyware is adware. The purpose of an adware program is to capture so-called "anonymous" data for targeted advertising. (See the Problems section below to see why this can cause serious issues.) Adware is usually just an annoyance, but in some cases can cause greater difficulties.

The less common second classification of spyware programs is called malware. Malware is any program designed to cause problems with the normal use of a computer or for the user of that computer. Examples of malware include viruses, Trojan horse programs, and certain forms of hijacking spyware. These forms of spyware are written to collect personal information such as passwords, credit card numbers, and social security numbers for identity theft and fraud. Many of these can change default program settings to allow an attacker access to the computer, or monitor a user's keystrokes to gain information. The information is then sent off to the attacker to use as they see fit.

Problems with spyware

Several problems present themselves when a user has spyware on their system.

Annoyance:
Spyware can be a huge annoyance to users. Created pop-up ads often appear - seemingly at random - when web pages are opened or closed. This can cause hours of wasted effort because many of the pop up ads create more pop up ads as they are closed, in an ever expanding cycle. One solution to this problem, a pop up blocker, is detailed later.

Pornographic advertising:
Spyware which creates targeted advertisements can be a problem. The targeted ads will be created from information such as websites and advertisements visited previously. If an adult user and a minor are using the same computer, this can be a problem. If the adult user visits a pornographic site, the minor could receive targeted advertisements which contain pornographic material. In some cases the targeting of ads can be for pornographic advertisements without anyone having visited adult sites.

Computer Resource Hijacking:
Some spyware allows the unauthorized use of computer resources. This can include running programs while a PC is not busy. However, increased use of a computer processor increases the wear and tear on the components, and reduces its functional lifetime. In some cases resources are used for malicious purposes, such as mailing spam or viruses, or actually using the computer to commit crimes.

Spyware Errors:
Programming errors in the way a piece of spyware is written can also cause problems. A piece of spyware may expire, yet keep trying to send information to a disconnected server. This would send error messages to the user, causing worry and irritation.

Removing installation:
Removing spyware can be a huge chore. Many spyware programs offer an "uninstallation" option which either does not work as advertised or actually installs more spyware.

Lose control of your PC :
Spyware can cause a user to lose control of their PC . Changes to the web browser's homepage and to other settings can be made without the user's knowledge or permission. These changes can include turning off security protection so the spyware can communicate with external resources, making them potentially very dangerous.

Wired Magazine - "Microsoft claims half of all computer crashes reported by its customers are caused by spyware and its equivalents."

Continued...