In Greece, a Trojan Horse was a clever ploy that was once used in order to win a war. Today, a computer Trojan can be just as ugly as it was back there in ancient Greece. This is because a Trojan will hide inside of a file that otherwise looks quite innocent. Once the virus is unleashed upon your computer it will break down your security. It will actually allow other people to view your credit card number, passwords and other such sensitive information.

Trojans can come from almost anywhere. Most commonly they are found whenever you download a video or music file online. Once you get a Trojan, you are in a fair amount of trouble.

So, how do you get rid of a Trojan? Well, you really should have taken the time to prevent getting it in the first place. This can be done by being extremely careful about the items that you download and only getting your files from trusted sources. However, if you already have a Trojan on your computer, then you will need to do a complete re-installation and thorough cleaning of your hard drive. This is a long, tedious process, but it is the only way in which you can be sure that the Trojan really is gone.

However, you are going to have to find software that specifically states that it deals with Trojans. This is because not all anti-virus software will attack a Trojan. For this reason, you will have to be careful about what you use. After all, you do not want to make the situation any worse than it already is.

Of course, you can also get some anti-virus software that will "attack" the Trojan. In this way, the software will deal with the Trojan for you.

One of the examples of a Trojan is a program named waterfalls.scr. This program was known for its free waterfall screensaver. The known name was disguised to computer users; upon execution of this program it would open computer ports. These open ports were used by hackers to access computers remotely. What makes these programs dangerous is its ability to hide in the computer’s registry and modify it. These are programmed to do damage to systems and networks. Some of the Trojan programs are harmless; due to this nature programs are divided into many categories.

1. Remote Access
2. E-mail Sending
3. Data Destruction
4. Downloader etc.

1. Can erase or overwrite data on a computer
2. Cryptoviral extortion attack
3. Corrupting files
4. Upload and download files
5. Spreading 'dropper' or 'vector' (viruses)
6. Creating Zombie Computer
7. Records keystroke on computer. This can be used to record password or financial information
8. Phishing attack
9. Interfering with hardware, such as opening and closing CD-ROM
10. Using e-mail address book for spam
11. Frequent re-starts of system
12. Damage system software etc.

1. Clear Internet temporary files
2. Use good anti-virus software to clean your system
3. In some case it will be necessary to reset your computer to your last backup or reset back to factory defaults
4. Avoid opening attachments from unknown senders
5. Install good firewall and antivirus software
6. Change password regularly
7. Take periodic backup of data and system
8. Avoid downloading free software

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