What is the Difference between Trojan Horse and virus?

Answer 1

Despite the fact that viruses and trojans are frequently confused, they are actually two very different types of unwanted pests.

A virus is a small program that "adds itself" onto an existing program, and forms a modified file. Because of this it is difficult to detect, as no new or suspicious files will initially appear on the infected system.

Once activated, a virus will usually spread itself onto other systems - either across a network, via email, through the internet, or even via disks and CDs.

A virus can delete or alter files and data, and may sometimes go to great lengths to remain undetected, and may often prove to be extremely difficult to remove. They often remain quite invisible to the unwary user, and may even disable anti-virus software to remain hidden and safe from detection and deletion.

A trojan on the other hand is a standalone program. It does not add itself onto existing files, nor does it try to replicated and spread to other systems and networks.

A trojan's main purpose it to make it's host system open to access, usually via the internet. A trojan may allow an unwanted person to see the files and data on the infected system. It may grant free access to the intruder, who may then be able to freely explore, view, modify and delete data from the hard drive. They may be able to intercept incoming and outgoing data, including emails, keystrokes, passwords, sensitive information and so on.

For the Trojan to be effective, it needs to be run at every reboot of the infected system. Because of this it may add entries to the registry or even the startup folder.

Removing the trojan tends to be quite simple. You simply delete the offending file, and remove all references to it. Detecting it, however, in the tens of thousands of files on most hard drives, is an altogether more difficult process.

Answer 2

The term Trojan horse is used while talking about computer infections. Trojan house is probably a name used to lure PC users in downloading malicious software

Answer 3

A Trojan virus gets in by being a harmless looking program, while the regular virus attacks by being in a link or by an email.

Answer 4

Yes, though not a usual one.