Trojan Horse

What Does Trojan Horse Mean?

A Trojan horse is a seemingly benign program that when activated, causes harm to a computer system.


A Trojan horse is also known as a Trojan virus or Trojan.

Techopedia Explains Trojan Horse

The Trojan horse is named for ancient Greece’s apparent gift of peace to the Trojans, when a giant wooden horse was secretly filled with Greek warriors. After the Trojans allowed the horse to enter their great city, the Greek warriors emerged from the horse gained control of the city of Troy.

The following are types of trojan horses:

  • Backdoor Trojan: opens a back door for a user to access a victim’s system at a later time
  • Downloader: This Trojan downloads malicious software and causes harm to the victim’s computer system.
  • Infostealer: This Trojan attempts to steal information from the victim’s computer.
  • Remote Access Trojan (RAT): This can be hidden in games or other programs of a smaller variety and give the attacker control of the victim’s computer.
  • Data Sending Trojan: This gives the perpetrator sensitive information like passwords or other information programmed to be hijacked.
  • Destructive Trojan: This destroys the victim’s files.
  • Proxy Trojan: As a proxy server, this allows the attacker to hijack a victim’s computer and conduct illegal activities from the victim’s computer.

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Margaret Rouse

Margaret is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical business audience. Over the past twenty years, her IT definitions have been published by Que in an encyclopedia of technology terms and cited in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine, and Discovery Magazine. She joined Techopedia in 2011. Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages.