ADSPY: Adware/Spyware, software that displays advertising or software that sends the users’ personal data to a third party without their knowledge or consent.

Adware: Adware (or spyware) is a small program that is designed to show advertisements (in various form and degrees of intrusiveness) on your computer. It often reports personal information back to its owners. As a result your sense of privacy can be violated.

Backdoor: A backdoor is a small malicious program that is used to gain access to a computer by bypassing the computer access security mechanisms. It gives the attacker almost unlimited rights. While it can be used to spy on a user, it is mainly used to install other malware on the system.

BHO: Browser Helper Objects are small programs that extend the functionality of Microsoft Internet Explorer. Many toolbars shown in Internet Explorer are BHOs. Spyware and browser hijackers frequently use BHOs to integrate themselves with Internet Explorer, and to display advertisements, capture data, etc. BHOs are often installed by small ActiveX-based files.

Browser Hijacker: Browser Hijackers are programs that attempt to alter homepage, searchpage and/or other browser settings. Some also install additional files that change these settings back on every restart (if you should try to revert to your old settings). Browser Hijackers may be installed by ActiveX controls on webpages.

Dialer: Certain services available in the internet have to be paid for. Genuine dialers are only installed on the user’s computer subject to the user’s consent, which must be given via a completely unambiguous and clearly visible labeling or request. Fraudulent dialers install themselves on computers unnoticed, by dubious means or even with deceptive intent and set the computer up to dial up through their number, so as to make money from the calls.

Dropper: A dropper is a component that has been designed to "install" some sort of malware (virus, backdoor, etc) to a target system. A few other malware files code compressed inside the dropper in such a way as to avoid detection by virus scanners. So detection of the whole dropper package is needed.

Heuristic: A technique designed to detect malware by empirical means but without having the specific data.

Hijacker: Hijacking is a type of network security attack in which the attacker takes control of a communication - just as an airplane hijacker takes control of a flight - between two entities and masquerades as one of them.

Malware: A generic name for all types of malicious programs: adware, backdoors, rogues, trojans, viruses and worms.

Misleading: The program reports false or exaggerated system security threats on the computer. The user is then prompted to pay for a full license of the application in order to remove the threats.

PHISH: Phishing is the criminally fraudulent process of attempting to acquire information such as usernames, passwords and credit card details by masquerading as a trustworthy entity (usually: popular social web sites, auction sites, online payment processors or IT administrators) ?in an electronic communication. Phishing is typically carried out by e-mail or instant messaging, and it often directs users to enter details at a fake website whose look and feel are almost identical to the legitimate one.

Rogue: A rogue program is a malicious program that is disguised, for instance, as trustworthy anti-spyware programs or registry cleaners. But these programs are only put on the market to scare you into buying these programs because they make exaggerated claims about the safety of your computer or, worse still, give erroneous scan results or put their own malware in your system.

Rogueware: Rogueware are meaningful files which in reality can be quite malicious. The most common type of Rogueware are fake anti virus/adware/spyware progams that once installed, say you have lots of viruses/malware installed and in order for the program to remove them you must pay for the full version. In the past, these programs typically spread by advertising on other sites with banners saying things like "1023 Viruses detected on your computer! Click here to fix it now!".

Rootkit: A rootkit is a software system that consists of a program or combination of several programs designed to hide or obscure the fact that a system has been compromised.

Spambot: A spambot is an automated computer program designed to assist in the sending of spam.

Spyware: Spyware is a type of malware that is installed surreptitiously on personal computers to collect information about users, their computer or browsing habits without their informed consent.

Tracking cookies: Tracking cookie is a small string of text stored on a user's computer by a web browser. A cookie consists of one or more name-value pairs containing bits of information such as user preferences, shopping cart contents, the identifier for a server-based session, or other data used by websites.

Trojan: A Trojan (or Trojan horse) is a small malicious program that pretends to have a particular function, but that only shows its real purpose after execution and that purpose is often destructive. Trojans cannot multiply themselves, which differentiates them from viruses and worms.

Unwanted: The program reports false or exaggerated system security threats on the computer.The user is then prompted to pay for a full license of the application in order to remove the threats.

Virus: A virus is a small malicious program that multiplies and is capable to attach itself to other programs after being executed. It then causes an infection and causes various degrees of damage to your computer.

Worm: A worm is often characterized as a malicious application that will use a host machine to infect other machines. Therefore worms can create enormous damage on networks with multiple computers.