code

A code is a rule for converting a piece of information into another object or action, not necessarily of the same sort.

In communications and information processing, code is a system of rules to convert information—such as a letter, word, sound, image, or gesture—into another form, sometimes shortened or secret, for communication through a communication channel or storage in a storage medium. An early example is an invention of language, which enabled a person, through speech, to communicate what they thought, saw, heard, or felt to others. But speech limits the range of communication to the distance a voice can carry and limits the audience to those present when the speech is uttered. The invention of writing, which converted spoken language into visual symbols, extended the range of communication across space and time.

The process of encoding converts information from a source into symbols for communication or storage. Decoding is the reverse process, converting code symbols back into a form that the recipient understands, such as English or/and Spanish.

A codec /ˈkəudek/ is a device or computer program which encodes or decodes a digital data stream or signal. Codec is a portmanteau [紧缩词,合并词] of coder-decoder. In electronic communications, an endec is a device which acts as both an encoder and a decoder on a signal or data stream, and hence is a type of codec. Endec is a portmanteau of encoder-decoder. Coder is a device that generates a code, often as a series of pulses while encoder is a device used to encode a signal either for cryptography or compression. 像无中生有和改头换面。

One reason for coding is to enable communication in places where ordinary plain language, spoken or written, is difficult or impossible. For example, semaphore, where the configuration of flags held by a signaler or the arms of a semaphore tower encodes parts of the message, typically individual letters, and numbers. Another person standing a great distance away can interpret the flags and reproduce the words sent.

Origin of P-V (nyu.edu)

Code may also refer to:

Computing

• Code (metadata), data elements whose allowable values can be represented as enumerated lists
• Code point, colloquially referred as a [character] code (in some encoding)
• Coding theory, branch of mathematics and computer science dealing with data transmission
• Computer code, set of instructions forming a computer program which is executed by a computer
• Encoding (memory), store and recall information
• Machine code, a sequence of instructions to a processor unit
• Source code, a sequence of statements and/or declarations written in some human-readable (usually as a text) computer programming language
• <code></code>, an HTML element

Science and technology

• Code (cryptography), device for hiding the meaning of a message
• Barcode [条形码], an optical, machine-readable representation of a numeric code that identifies the object to which it is attached. 二维码: QR Code. The “QR” in QR Codes stands for “Quick Response.”
• Diagnosis code, used to translate medical conditions into statistical codes, also used for the purpose of health care planning and reimbursement
• Genetic code, a correspondence between the structures of messenger RNA and proteins
• Hospital emergency codes, used in hospitals worldwide to alert staff to various emergencies
• Morse code, a method which humans can transmit letters using only short and long pulses
• Nomenclature [命名法] codes, rulebooks of scientific naming convention
• Serial code or serial number

Society and law

• Code (law), body of law written and enforced by a sovereign state
• Legal code (municipal), a body of law written by a regional or local governmental entity, such as a U.S. state, a Canadian province, a German Bundesland, or a municipality. The function of a Bundesland Germany is a federal state. This means that it is a union of different provinces or states that are partially self-governed, but are all considered to be German.
• Building code, set of rules that specify the minimum standards for constructed objects
• Code name, a word or name used to refer to another name, word, project or person
• Ethical code, adopted by a profession, by a governmental or quasi-governmental organ, or by a trade group or other organization

Others

• Code and Other Laws of Cyberspace, a 1999 book by Lawrence Lessig
• Code of non-infringement or The Code, of clowns and other performers
• Konami Code, a cheat code which appears in mainly Konami video games
• Code, a unit of scale in model railroading

六级/考研单词: convert, gesture, prolong, medium, utter, reverse, compute, digit, data, electron, seldom, pulse, configuration, interpret, reproduce, mathematics, instruct, execute, diagnose, translate, heal, alert, workforce, transmit, convention, serial, enforce, sovereign, illicit, municipal, entity, province, construct, ethic, cyberspace, clown, cheat, railroad