Substitution cipherIn cryptography, a substitution cipher is a method of encrypting that creates the ciphertext (its output) by replacing units of the plaintext (its input) in a defined manner, with the help of a key; the "units" may be single letters (the most common), pairs of letters, triplets of letters, mixtures of the above, and so forth. The receiver deciphers the text by performing the inverse substitution process to extract the original message.
CodebookA codebook is a type of document used for gathering and storing cryptography codes. Originally, codebooks were often literally books, but today "codebook" is a byword for the complete record of a series of codes, regardless of physical format. CryptographyIn cryptography, a codebook is a document used for implementing a code. A codebook contains a lookup table for coding and decoding; each word or phrase has one or more strings which replace it.
CryptanalysisCryptanalysis (from Greekkryptós'hidden' and analýein'to analyze') refers to the process of analyzing information systems in order to understand hidden aspects of the systems. Cryptanalysis is used to breach cryptographic security systems and gain access to the contents of encrypted messages, even if the cryptographic key is unknown.Beale ciphersSet of three ciphertexts Cover of The Beale Papers The Beale ciphers are a set of three ciphertexts, one of which allegedly states the location of a buried treasure of gold, silver and jewels estimated to be worth over $60 million as of January 2025[update].Code (cryptography)Method used to encrypt a message A portion of the "Zimmermann Telegram" as decrypted by British Naval Intelligence codebreakers. The word Arizona was not in the German codebook and had therefore to be split into phonetic syllables. Partially burnt pages from a World War II Soviet KGB two-part codebook In cryptology, a code is a method used to encrypt a message that operates at the level of meaning; that is, words or phrases are converted into something else.
CipherIn cryptography, a cipher (or cypher) is an algorithm for performing encryption or decryption—a series of well-defined steps that can be followed as a procedure. An alternative, less common term is encipherment. To encipher or encode is to convert information into cipher or code.EspionageEspionage, spying, or intelligence gathering, as a subfield of the intelligence field, is the act of obtaining secret, confidential, or in some way valuable information. Such information is also referred to as intelligence. A professional trained in conducting intelligence operations by their government may be employed as an intelligence officer. Espionage may be conducted in a foreign country, domestically or remotely.PlaintextIn cryptography, plaintext usually means unencrypted information pending input into cryptographic algorithms, usually encryption algorithms. This usually refers to data that is transmitted or stored unencrypted. OverviewWith the advent of computing, the term plaintext expanded beyond human-readable documents to mean any data, including binary files, in a form that can be viewed or used without requiring a key or other decryption device.
The War of the WorldsThe War of the Worlds is a science fiction novel by English author H. G. Wells about an attempted invasion of Earth by beings from the planet Mars with much greater intelligence and more advanced weapons than humans. The Martians intend to eliminate mankind and conquer Earth because their own older and smaller world has reached the "last stage of exhaustion".
World War IIGlobal conflict from 1939 to 1945BelligerentsAlliesAxisCommanders and leadersMain Allied leaders: Joseph StalinFranklin D. RooseveltWinston ChurchillChiang Kai-shekMain Axis leaders: Adolf HitlerHirohitoBenito MussoliniCasualties and losses 60–75 million deaths (military and civilian) World War II, or the Second World War (1 September 1939 – 2 September 1945), was a global conflict between two coalitions: the Allies and the Axis powers.
H. G. WellsHerbert George Wells (21 September 1866 – 13 August 1946) was an English writer, prolific in many genres. He wrote more than forty novels and dozens of short stories. His non-fiction output included works of social commentary, politics, history, popular science, satire, biography, and autobiography.Key (cryptography)A key in cryptography is a piece of information, usually a string of numbers or letters that are stored in a file, which, when processed through a cryptographic algorithm, can encode or decode cryptographic data. Based on the used method, the key can be different sizes and varieties, but in all cases, the strength of the encryption relies on the security of the key being maintained.*As an Amazon Associate I earn from qualifying purchases.