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Definitions

Your Glossary to Virus and Spyware terminology

Online security threats are real and dangerous to your computer system and personal data. Here are definitions of some of the more insidious threats:

Computer Viruses:
A computer virus is a program that can copy itself and infect a computer. It can spread from one computer to another when it is sent over a network, the Internet, via email, or carried on a removable device like a CD, DVD or USB drive—all without the knowledge of the user.
Trojan Horses:
A computer Trojan Horse is software that disguises itself as valuable and useful software available for download on the Internet. Most people are fooled by this ploy and end up dowloading the virus disguised as some other application. A good antivirus program can help prevent Trojan Horses.
Computer Worms:
Computer Worms are like a virus; they are designed to copy themselves from one computer to another via a network connection and without human interaction. Unlike a virus, a worm can copy itself automatically. They can replicate themselves in large numbers and send out copies to everyone in your email address book and continue to send themselves from those address books. They can spread quickly and cause long waits when loading Web pages.
Spyware:
Spyware is a type of malware that gets installed on computers and collects bits of information about users without their knowledge. Spyware is usually hidden from the user, and can be difficult to detect. Typically, it is secretly installed on the user's personal computer. On some occasions, the owner of a shared, corporate, or public computer installs spyware is installed in order to furtively monitor other users. The application of spyware can extend beyond simple monitoring. Programs can collect various types of personal information, such as Internet surfing habits and sites that have been visited, but can also interfere with user control of the computer.
Antivirus Software:
Antivirus software is used to prevent, detect, and remove malware, including computer viruses, worms, and Trojan horses. Some products also prevent and remove adware, spyware, and other forms of malware.
Phishing
Phishing is the act of sending an email to a computer user falsely claiming to be a legitimate business in an attempt to scam the user into yielding private information to be used for identity theft. The email tells the user to visit a website disguised to look real where they are asked to update personal information, such as passwords and credit card, social security, and bank account numbers, that the legitimate organization already has. This website, though, is bogus and set up only to steal the user’s information.
Firewall
A firewall is part of a computer system or network that is designed to block unauthorized access but permitting authorized communications. It is a device or set of devices that are constructed to permit or deny computer applications based upon a set of rules and other criteria. Firewalls can be either hardware or software, or a combination of both.
Spam
Spam is the practice of flooding the Internet with many copies of the same email or instant message in an attempt to impose the message on people who would not otherwise choose to receive it. Most spam is commercial advertising, often for suspicious products, get-rich-quick schemes, or quasi-legal services.
Adware
Adware is a software package that automatically plays, displays, or downloads advertisements to a computer after the software is installed on it or while the application is being used. Some types are adware are classified as privacy-invasive software.
False Positive
A false positive occurs when a pattern of code in a file matches the same pattern contained In a virus signature. This can occur due to a faulty signature or it can occur after improper disinfection by the same or different antivirus scanner.
Host
This term describes the computer file to which a virus attaches itself. Most viruses run when the computer or user tries to execute the host file.
Hacker
Hackers create and modify computer software and hardware, including computer programming, administration, and security-related items. This can be done for either negative or positive reasons. Criminal hackers create malware in order to commit crimes.
Malware
Malware is a general term to describe malicious software such as viruses, Trojan horses, spyware, and other malicious active content.