Decrypted Secrets -

: Reviewers frequently cite it as "the best single book on cryptology today". Bauer, a renowned German professor, offers unique insights—such as how specific American ciphers were compromised in WWII—that might be sensitive for US or UK-based authors to publish.

: The text is "spiced" with historical anecdotes and personal stories, particularly focusing on the first half of the 20th century. Decrypted Secrets

– Focuses on the creation of codes and ciphers. It details various encryption steps, including simple and polygraphic substitution, linear substitution, transposition, and polyalphabetic systems. : Reviewers frequently cite it as "the best

Ideal as a classic reference work and supplementary text for university-level courses. – Focuses on the creation of codes and ciphers

Excellent for those interested in the history of codemaking/breaking in the 20th century.

Decrypted Secrets: Methods and Maxims of Cryptology - Amazon UK