The adware and spyware definitions list is very long. But the definitions listed below are the most common ones. This is a glossary of spyware facts and terms so you'll know what these malicious programs are and what they can do to your computer.
Adware
Adware components are generally installed along with a shareware or freeware programs you download. The adware developer creates pop up windows that generate advertisement revenue for them. Most adware components are actually installed with consent from the user. This happens because most people never read the end-user license agreement that comes with software.
Spyware
Spyware is most often installed bundled with freeware or shareware, much like adware. Spyware programs gather and transmit sensitive and personal information about your online behavior to an unknown party. The data is collected without you even knowing it happened. By the time you discover it, the damage is done and the hacker is long gone.
Browser Hijackers
Browser hijackers are innocently installed as helpful browser toolbars. They can alter your browser settings and can change your default home page to point to a site that generates revenue for the hijacker.
Trojan Horse Programs
Trojan horse programs sneak into your system and run without you realizing it similar to spyware. Programmers use these programs for any number of malicious uses and not one of them you would approve of. The good thing is Trojan horse programs do not duplicate themselves.
Tracking cookies
Tracking cookies are files with small amounts of data like passwords and settings. Tracking cookies can provide a benefit to you especially if you revisit the same web sites. But in the wrong hands, cookies are used to track your Internet behavior without your knowledge or consent and provides marketers with private information about you.
Keyloggers
Keyloggers are programs that run in the background silently recording all your keystrokes. Once the keystrokes are logged, the hacker uses a remote keyloggers program to retrieve the data later. The hacker can get your passwords, credit card numbers and any personal information on your computer.
Malware
The definition of malware is any malicious software or program that will harm your computer. Computer viruses, worms and Trojans are all considered malware, but several other types of programs may also be included under the term.
Password Cracker
A password cracker is simply a program used to decrypt a password or password file. Security administrators use password crackers for legitimate use by using them to improve system security. But the dangers when a hacker gets a program like this is unimaginable.
There are many other spyware definitions including scumware, annoyanceware, parasites and the list continues to grow daily.