Trojan horse is one of the main symbols of the famous Trojan war, used as strategy by the Greeks to defeat the Trojans.
According to the story narrated in Homer's “Iliad”, the Trojan Horse was made of wood and completely hollow inside.
Trojan Horse Representation
the greek warrior Odysseus he would have had the idea of building a gigantic horse and presenting the Trojans, as a symbolic gesture of surrender to the war.
The Trojans accepted the “gift” and took the horse inside the walls of Troy. All the soldiers drank and celebrated the enemy's surrender, and when everyone was asleep, hundreds of Greek soldiers got out of their horse and attacked the city.
To help destroy their enemies, the warriors led by Odysseus opened the city gates, enabling a full Greek invasion of Troy, which was completely destroyed.
From this story came the popular expression “Greek's gift”, when someone is referring to something they have won but will not be useful or will cause problems.
An example of a “Greek's gift” is someone who is allergic to cats receiving one as a birthday present, as the animal would bring more complications than benefits to the recipient.
See also the meaning of the expression "please Greeks and Trojans”.
Trojan Horse Virus
Also known as trojan horse, this is a type of virus that is intended to "open the doors" so that a hacker can infect your computer's operating system.
The name came from an allusion to the Greek tale, because this virus is hidden inside another program, as if it were harmless.
Trojans can interfere with the navigability and good performance of the computer, in addition to jeopardizing the security of your user's data.
To avoid or eliminate trojan horses, it is advisable to install software anti-trojan or anti-malware, that are properly certified.
See also the meaning of hacker.