treu
loyal / faithful
To be loyal, reliable, and devoted to a person, cause, or belief and not turn away from it.
Ein Hund gilt oft als der treueste Freund des Menschen.
A dog is often considered a person's most faithful friend.

loyal / faithful
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loyal / faithful
To be loyal, reliable, and devoted to a person, cause, or belief and not turn away from it.
Ein Hund gilt oft als der treueste Freund des Menschen.
A dog is often considered a person's most faithful friend.

'Treu' means 'loyal' or 'faithful' and is often confused with the English word 'true'. However, 'true' in German means 'wahr' (true) or 'richtig' (correct).
Er ist ein treuer Freund, auf den man sich immer verlassen kann.
He is a loyal friend whom you can always rely on.
The adjective 'treu' (loyal/faithful) is closely related to the noun 'die Treue' (loyalty/faithfulness). 'Die Treue' describes the quality or state of being loyal.
Seine Treue zu seinen Prinzipien ist bewundernswert.
His loyalty to his principles is admirable.
To express whom one is loyal to, 'treu' is used with the dative. The fixed structure is: 'jemandem treu sein' (to be faithful to someone) or 'jemandem treu bleiben' (to remain faithful to someone).
Sie ist ihrem Mann immer treu geblieben.
She always remained faithful to her husband.
In the context of art, literature, or copies, 'treu' means that something corresponds very closely to the original. Typical collocations are 'eine treue Kopie' (a faithful copy), 'eine treue Übersetzung' (a faithful translation), or 'eine treue Wiedergabe' (a faithful reproduction).
Diese Software erstellt eine treue Kopie der Originaldatei.
This software creates a faithful copy of the original file.
exact / precise
'genau' and 'treu' can both refer to something corresponding to a model or source. 'genau' is the general word for precise, correct, and without deviation. In this meaning, 'treu' is used especially with a model, an original, or a description, for example 'werktreu' (faithful to the work) or 'detailgetreu' (true to detail). Then it means: close to the original. Learners may confuse the words because in such cases 'treu' also means 'corresponding exactly'. In normal everyday language, 'genau' is broader and simpler. 'treu' fits better when you want to emphasize the connection to an original.

Der Film bleibt der Vorlage treu und ändert nur wenige Szenen.
The film stays faithful to the original and changes only a few scenes.
Die Kopie ist sehr genau, sogar die kleinen Linien stimmen.
The copy is very precise; even the small lines match.