Security CD - Definitions
Virus: A type of program designed to do two basic things: infect and spread. Viruses can damage your computer software, destroy and corrupt your files, damage Windows, decrease the performance of your computer, alter anything they want, or be a plain annoyance. In addition to being annoying, they try to spread by multiple methods such as harvesting e-mails from your computer, and e-mail everyone in your address book.
Trojan: A specific type of virus that allows the creator to take control over your computer. When infected with a trojan, it will typically attempt to: destroy any Anti Virus software on your computer, let the creator know you are infected, and then wait until told to do something. Trojans give the creator complete control over your computer: they can open and close your CD-ROM tray, take over your keyboard or mouse, alter settings, install or delete things, and steal passwords and confidential information. Trojans allow someone else to gain complete control over your computer, and do as they please with it.
Adware: A type of program that displays advertising on your computer. It may be in the form of a popup ad even when you're not browsing the internet, change of your internet homepage, random redirections to webpages you didn't intend to go to, or hijacking of your internet settings.
Spyware: A type of program that secretly spies on the computer user. It can record your keyboard activity (possibly including typed passwords and credit card numbers), know where you've been online, and monitor all use of the computer. It then sends this information back to the creator who in turn sells this information for profit.