- The Enigma machine is a cipher device developed and used in the early- to mid-20th century to protect commercial, diplomatic, and military communication. It was employed extensively by Nazi Germany during World War II, in all branches of the German military. The Enigma machine was considered so secure that it was used to encipher the most top-secret messages.
- Hadith (Wikipedia)
Ḥadīth (/ˈhædɪθ/ or /hɑːˈdiːθ/; Arabic: حديث, ḥadīṯ, Arabic pronunciation: [ħadiːθ]; pl. aḥādīth, أحاديث, ʾaḥādīṯ, Arabic pronunciation: [ʔaħaːdiːθ], lit. ’talk’ or ‘discourse’) or Athar (Arabic: أثر, ʾAṯar, lit. ‘remnant’ or ’effect’) refers to what most Muslims and the mainstream schools of Islamic thought believe to be a record of the words, actions, and the silent approval of the Islamic prophet Muhammad as transmitted through chains of narrators. In other words, the ḥadīth are attributed reports about what Muhammad said and did (see: Oral tradition).