Biuro Szyfrów

English: The Biuro Szyfrów (Cipher Bureau ) was the Polish agency concerned with cryptology between World Wars I and II. The Bureau enjoyed notable successes against Soviet cryptography during the Polish-Soviet War, helping to preserve Poland's independence. Beginning in December 1932, the Cipher Bureau broke the German Enigma cipher and overcame the ever-growing structural and operating complexities of the evolving Enigma machine.

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  Biuro Szyfrów
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  Marian Rejewski
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  Enigma, on display in Warszawa
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  Cyclometer
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  Zygalski (perforated) sheets