Now they are all over the internet and can be the end for you. A Trojan Horse! When most computer users think of a Trojan horse they usually think of a computer virus. This is, however, incorrect because a virus and Trojan horse are two different nuisances that are known as Malware (Malicious Software). Trojan horses receive their moniker by being disguised as different programs, even anti-virus programs which make people think they are there to help but do the exact opposite. Trojan Horses are categorized in to seven different varieties based on how they get in and the damage that can be done. The first four Trojans that will be explained are the most damage dealing to a user and their system and the last three deal damage to other systems.

The first and most dangerous kind of Trojan horse are called Remote Access Trojans, also known as (RATS). (RATS) can be used to gather private information such as a credit cards, bank accounts, and even social security numbers. (RATS) can also take control of a computer, making disc trays open or causing your screen to flip around. The second variety are known as Data Sending Trojans, a type of Trojan which will focus only on collecting a person’s personal data including contact lists. This Trojan will often use a "Keylogger" which keeps a record of every single keystroke that person has made. The third is called a Destructive Trojan which is the closest a Trojan can get to being a virus as it is meant to delete files and slowly wither away a computer similar to a virus. Security Software Disabler Trojans are used in part with other Trojans as they are meant to disable any anti-virus programs and security a user is running without the user knowing.

The last three Trojan horse varieties are unique as they do not directly attack the victims computer but use victims computers as a means to do harm to others. Proxy Trojans and FTP Trojans both allow the attacker to use a victim’s computer to conduct credit card fraud and other illegal activities using special connections. The seventh and constantly changing Trojan is called a Denial-of-service attack (DoS). This Trojan is similar to the previous two Trojans as they use a special connection to cause trouble but on a larger scale. (DoS) will attack a whole network and bring everything to a crawl or halt. So be careful what programs you download and keep your anti-virus software updated.