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ROT13
ROT13 ("rotate by 13 places", sometimes hyphenated ROT-13) is a simple letter substitution cipher that replaces a letter with the 13th letter after it in the alphabet. ROT13 is a special case of the Caesar cipher which was developed in ancient Rome. Because there are 26 letters (2×13) in the basic Latin alphabet, ROT13 is its own inverse; that is, to undo ROT13, the same algorithm is applied, so the same action can be used for encoding and decoding. The algorithm provides virtually no cryptographic security, and is often cited as a canonical example of weak encryption. ROT13 is used in online forums as a means of hiding spoilers, punchlines, puzzle solutions, and offensive materials from the casual glance. ROT13 has inspired a variety of letter and word games online, and is frequently mentioned in newsgroup conversations. Description Applying ROT13 to a piece of text merely requires examining its alphabetic characters and replacing each one by the letter 13 places further al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ROT13 Table With Example
ROT13 ("rotate by 13 places", sometimes hyphenated ROT-13) is a simple letter substitution cipher that replaces a letter with the 13th letter after it in the alphabet. ROT13 is a special case of the Caesar cipher which was developed in ancient Rome. Because there are 26 letters (2×13) in the ISO basic Latin alphabet, basic Latin alphabet, ROT13 is its own inverse function, inverse; that is, to undo ROT13, the same algorithm is applied, so the same action can be used for encoding and decoding. The algorithm provides virtually no cryptography, cryptographic security, and is often cited as a canonical example of weak encryption. ROT13 is used in online forums as a means of hiding spoiler (media), spoilers, punch line, punchlines, puzzle solutions, and profanity, offensive materials from the casual glance. ROT13 has inspired a variety of letter and word games online, and is frequently mentioned in newsgroup conversations. Description Applying ROT13 to a piece of text merely require ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Substitution Cipher
In cryptography, a substitution cipher is a method of encrypting in which units of plaintext are replaced with the ciphertext, 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. Substitution ciphers can be compared with transposition ciphers. In a transposition cipher, the units of the plaintext are rearranged in a different and usually quite complex order, but the units themselves are left unchanged. By contrast, in a substitution cipher, the units of the plaintext are retained in the same sequence in the ciphertext, but the units themselves are altered. There are a number of different types of substitution cipher. If the cipher operates on single letters, it is termed a simple substitution cipher; a cipher that operates on larger groups of letters ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Involution (mathematics)
In mathematics, an involution, involutory function, or self-inverse function is a function that is its own inverse, : for all in the domain of . Equivalently, applying twice produces the original value. General properties Any involution is a bijection. The identity map is a trivial example of an involution. Examples of nontrivial involutions include negation (x \mapsto -x), reciprocation (x \mapsto 1/x), and complex conjugation (z \mapsto \bar z) in arithmetic; reflection, half-turn rotation, and circle inversion in geometry; complementation in set theory; and reciprocal ciphers such as the ROT13 transformation and the Beaufort polyalphabetic cipher. The composition of two involutions ''f'' and ''g'' is an involution if and only if they commute: . Involutions on finite sets The number of involutions, including the identity involution, on a set with elements is given by a recurrence relation found by Heinrich August Rothe in 1800: :a_0 = a_1 = 1 and a_n = a_ + ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spoiler (media)
A spoiler is an element of a disseminated summary or description of any narrative that reveals plot elements. Typically, the details of the conclusion of the plot, including the climax and ending, are especially regarded as spoiler material. It can also be used to refer to any piece of information regarding any part of a given media that a potential consumer was not intended to know beforehand. History One of the first print uses of the term was in the April 1971 issue of '' National Lampoon'', in which an article by Doug Kenney entitled "Spoilers" revealed the endings of famous films and movies. Kenney wrote: "Spoilers! What are they? Simply the trick ending to every mystery novel and movie you’re ever liable to see. Saves time and money!" The term spoiler was introduced in the early days of the Internet, and came to prominence in newsgroup conversations. It is still common in internet articles and social media discussions. Early rules of netiquette insisted that spoilers cou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johann Ernst Elias Bessler
Johann Ernst Elias Bessler (''ca''. 1680 – 30 November 1745), known as Orffyreus or Orffyré, was a German entrepreneur who claimed to have built several perpetual motion machines. Those claims generated considerable interest and controversy among some of the leading natural philosophers of the day, including Gottfried Wilhelm Leibniz, Johann Bernoulli, John Theophilus Desaguliers, and Willem 's Gravesande. The modern scientific consensus is that Bessler perpetrated a deliberate fraud, although the details of this have not been satisfactorily explained. Life and career Bessler was born to a peasant family in Lusatia, Upper Lusatia, in the German Electorate of Saxony, ''circa'' 1680. He went to school in Zittau, where (according to his own account) he excelled in his studies and became a favorite of Christian Weise, the rector of the local Gymnasium (Germany), ''Gymnasium''. After he left school he began to travel widely, seeking his fortune. Having saved an Alchemy, alchemis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reciprocal Cipher
Symmetric-key algorithms are algorithms for cryptography that use the same cryptographic keys for both the encryption of plaintext and the decryption of ciphertext. The keys may be identical, or there may be a simple transformation to go between the two keys. The keys, in practice, represent a shared secret between two or more parties that can be used to maintain a private information link. The requirement that both parties have access to the secret key is one of the main drawbacks of symmetric-key encryption, in comparison to public-key encryption (also known as asymmetric-key encryption). However, symmetric-key encryption algorithms are usually better for bulk encryption. They have a smaller key size, which means less storage space and faster transmission. Due to this, asymmetric-key encryption is often used to exchange the secret key for symmetric-key encryption. Types Symmetric-key encryption can use either stream ciphers or block ciphers. * Stream ciphers encrypt the digits ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryptography
Cryptography, or cryptology (from grc, , translit=kryptós "hidden, secret"; and ''graphein'', "to write", or ''-logia'', "study", respectively), is the practice and study of techniques for secure communication in the presence of adversarial behavior. More generally, cryptography is about constructing and analyzing protocols that prevent third parties or the public from reading private messages. Modern cryptography exists at the intersection of the disciplines of mathematics, computer science, information security, electrical engineering, digital signal processing, physics, and others. Core concepts related to information security ( data confidentiality, data integrity, authentication, and non-repudiation) are also central to cryptography. Practical applications of cryptography include electronic commerce, chip-based payment cards, digital currencies, computer passwords, and military communications. Cryptography prior to the modern age was effectively synonymo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Netscape Communicator
Netscape Communicator (or ''Netscape 4'') is a discontinued Internet suite produced by Netscape Communications Corporation, and was the fourth major release in the Netscape line of browsers. It was first in beta in 1996 and was released in June 1997. Netscape Communicator addressed the problem of Netscape Navigator 3.x being used as both the name of the suite and the browser contained within it by renaming the suite to Netscape ''Communicator''. It included more groupware features intended to appeal to enterprises. In February 1998, Netscape announced that Mozilla.org would co-ordinate the development of Netscape Communicator 5 as "a dedicated team within Netscape with an associated Web site that will promote, foster and guide open dialog and development of Netscape's client source code." However, the aging Communicator code proved to be difficult to work with, so it was abandoned. The whole source code of Communicator was re-written by Mozilla, who were then testing it as Mozill ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plaintext
In 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. Overview With 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. Information—a message, document, file, etc.—if to be communicated or stored in an unencrypted form is referred to as plaintext. Plaintext is used as input to an encryption algorithm; the output is usually termed ciphertext, particularly when the algorithm is a cipher. Codetext is less often used, and almost always only when the algorithm involved is actually a code. Some systems use multiple layers of encryption, with the output of one encryption algorithm becoming "plaintext" input for the next. Secure handling Insecure handling of p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Data Encryption Standard
The Data Encryption Standard (DES ) is a symmetric-key algorithm for the encryption of digital data. Although its short key length of 56 bits makes it too insecure for modern applications, it has been highly influential in the advancement of cryptography. Developed in the early 1970s at IBM and based on an earlier design by Horst Feistel, the algorithm was submitted to the National Bureau of Standards (NBS) following the agency's invitation to propose a candidate for the protection of sensitive, unclassified electronic government data. In 1976, after consultation with the National Security Agency (NSA), the NBS selected a slightly modified version (strengthened against differential cryptanalysis, but weakened against brute-force attacks), which was published as an official Federal Information Processing Standard (FIPS) for the United States in 1977. The publication of an NSA-approved encryption standard led to its quick international adoption and widespread academic scrutiny. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Encryption
In cryptography, encryption is the process of encoding information. This process converts the original representation of the information, known as plaintext, into an alternative form known as ciphertext. Ideally, only authorized parties can decipher a ciphertext back to plaintext and access the original information. Encryption does not itself prevent interference but denies the intelligible content to a would-be interceptor. For technical reasons, an encryption scheme usually uses a pseudo-random encryption key generated by an algorithm. It is possible to decrypt the message without possessing the key but, for a well-designed encryption scheme, considerable computational resources and skills are required. An authorized recipient can easily decrypt the message with the key provided by the originator to recipients but not to unauthorized users. Historically, various forms of encryption have been used to aid in cryptography. Early encryption techniques were often used in military ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
