Trojan
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Trojan
A computer program that is disguised as a useful application but runs harmful functions in the background, such as stealing data or giving an attacker access to the system.
Er hat sich beim Herunterladen einer Software einen Trojaner eingefangen, der nun seine Passwörter ausspäht.
He picked up a Trojan while downloading software, and it is now spying on his passwords.
The computer meaning is a metaphor based on the Greek legend of the Trojan War. Just like the Trojan Horse, which was disguised as a gift but hid soldiers, a computer Trojan disguises itself as a useful program in order to cause damage.
Die Geschichte des Trojanischen Pferdes erklärt die Namensgebung für die Schadsoftware.
The story of the Trojan Horse explains the naming of the malware.
The two meanings can be distinguished very easily by context. If it is about computers, software, or the internet, the harmful program is always meant. If it is about history, antiquity, or mythology, the inhabitants of Troy are meant.
Mein Antivirenprogramm hat einen Trojaner auf meinem Laptop gefunden.
My antivirus program found a Trojan on my laptop.
In the computer context, there are fixed expressions. You can 'sich einen Trojaner einfangen' (pick up/get infected with a Trojan), a program can 'einen Trojaner enthalten' (contain a Trojan), or you have to 'seinen Computer vor Trojanern schützen' (protect your computer from Trojans).
Sei vorsichtig mit E-Mail-Anhängen, damit du dir keinen Trojaner einfängst.
Be careful with email attachments so that you don't pick up a Trojan.
virus
'das Virus' and 'der Trojaner' can both be harmful programs on a computer. That is why they are easy to confuse. A computer virus mainly spreads by itself and can damage files or systems. A Trojan, on the other hand, disguises itself as a useful program but secretly does something harmful, such as stealing data. If you are speaking generally about harmful software, 'Virus' is often understood in everyday language. 'Trojaner' is more precise when the disguise as a normal program is important.
Der Trojaner sah wie ein kostenloses Spiel aus, hat aber Passwörter gestohlen.
The Trojan looked like a free game, but it stole passwords.
Tim findet in einer E-Mail ein Virus und öffnet den Anhang nicht.
Tim finds a virus in an email and does not open the attachment.