What is a Trojan?

What is a Trojan?
A Trojan is a type of program that enables a hacker to intrude and make changes to your computer. It is a threat in disguise. Like the Trojan horse popular in the Greek history, it appears safe (in the form of software program and e-mail attachment). But once opened, the Trojan may install itself on your computer and gain access without your consent. Generally, the initial objective of a Trojan is to browse your hard drive to determine anything of worth such as credit card information, passwords, confidential documents, email addresses, confidential designs or pictures, or even calendar information regarding the user’s whereabouts. Once found to be a potential source, the intruder then gets inside and manages your files totally. The intruder can do the following: rename, create, delete, view and even transfer files to or from your computer. Trojans will enable the intruder to open and close your CD-ROM drive, spam and gain control to your keyboard and cursor. Trojans can also use a program manager that will allow the intruder to install, execute, open or close any software programs. Indeed, it is big threat to security. How does it affect your computer?
The business starts first by the user installing the Trojan itself. This is done by deceiving the user with a seemingly useful system enhancement or perhaps a free game containing Trojans. By installing a free game, for example, Trojan will be automatically installed too. Trojans can also come in common disguises such as files from unknown sources, e-mail attachment from unknown sources, and files from any online activity client like ICQ. Once contaminated by Trojan, any distant user will inevitably have free access. The dirty work then starts. Other types of Trojans are: Remote Access Trojans, Mail Trojans, FTP Trojans, Telnet Trojans, Keylogger Trojans, Fake Trojans, and Form Trojans.Protect your Computer from Trojans
Trojans can also be distributed as email attachments, or bundled with other software programs. You should always be wary of opening attachments and downloading programs from the Internet unless you are sure it is from a secure and trusted source. If possible, confirm with the sender.
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