A programming language is an artificial language Language is a term most commonly used to refer to so-called "natural languages" — the spoken forms of communication ubiquitous among humankind. By extension the term also refers to the type of thought process which creates and uses language. Essential to both meanings is the systematic creation, maintenance and use of systems of designed to express computations Computation is a general term for any type of process, algorithm or measurement; this often includes but is not limited to digital data. This includes phenomena ranging from human thinking to calculations with a more narrow meaning. Computation is a process following a well-defined model that is understood and can be expressed in an algorithm, that can be performed by a machine A machine is a device that uses energy to perform some activity. In common usage, the meaning is that of a device having parts that perform or assist in performing any type of work. A simple machine is a device that transforms the direction or magnitude of a force without consuming any energy. The word "machine" is derived from the Latin, particularly a computer A computer is a programmable machine that receives input, stores and manipulates data//information, and provides output in a useful format. Programming languages can be used to create programs A program is list of instructions written in a programming language that is used to control the behavior of a machine, often a computer that control the behavior of a machine, to express algorithms In mathematics, computer science, and related subjects, an algorithm is an effective method for solving a problem expressed as a finite sequence of instructions. Algorithms are used for calculation, data processing, and many other fields precisely, or as a mode of human communication.
Many programming languages have some form of written specification of their syntax In linguistics, syntax is the study of the principles and rules for constructing sentences in natural languages (form) and semantics Semantics is the study of meaning. It typically focuses on the relation between signifiers, such as words, phrases, signs and symbols, and what they stand for (meaning). Some languages are defined by a specification document. For example, the C C is a general-purpose computer programming language developed in 1972 by Dennis Ritchie at the Bell Telephone Laboratories for use with the Unix operating system programming language is specified by an ISO The International Organization for Standardization , widely known as ISO (pronounced /ˈaɪsoʊ/ EYE-soe), is an international-standard-setting body composed of representatives from various national standards organizations. Founded on 23 February 1947, the organization promulgates worldwide proprietary industrial and commercial standards. It has Standard. Other languages, such as Perl Perl is a high-level, general-purpose, interpreted, dynamic programming language. Perl was originally developed by Larry Wall in 1987 as a general-purpose Unix scripting language to make report processing easier. Since then, it has undergone many changes and revisions and become widely popular amongst programmers. Larry Wall continues to oversee, have a dominant implementation Many combinations of interpretation and compilation are possible, and many modern programming language implementations include elements of both. For example, the Smalltalk programming language is conventionally implemented by compilation into bytecode, which is then either interpreted or compiled by a virtual machine. This implementation strategy that is used as a reference.
The earliest programming languages predate the invention of the computer Before the development of the general-purpose computer, most calculations were done by humans. Tools to help humans calculate were then called calculating machines, by proprietary names, or even as they are now, calculators. It was those humans who used the machines who were then called computers; they are pictures of enormous rooms filled with, and were used to direct the behavior of machines such as Jacquard looms The Jacquard loom is a mechanical loom, invented by Joseph Marie Jacquard in 1801, that simplifies the process of manufacturing textiles with complex patterns such as brocade, damask, and matelasse. The loom is controlled by punchcards with punched holes, each row of which corresponds to one row of the design. Multiple rows of holes are punched on and player pianos A player piano is a self-playing piano, containing a pneumatic or electro-mechanical mechanism that operates the piano action via pre-programmed music perforated paper, or in rare instances, metallic rolls. The rise of the player piano grew with the rise of the mass-produced piano for the home in the late 19th and early 20th century (see Harvey. Thousands of different programming languages have been created, mainly in the computer field, with many more being created every year. Most programming languages describe computation in an imperative In computer science, imperative programming is a programming paradigm that describes computation in terms of statements that change a program state. In much the same way that imperative mood in natural languages expresses commands to take action, imperative programs define sequences of commands for the computer to perform style, i.e., as a sequence of commands, although some languages, such as those that support functional programming In computer science, functional programming is a programming paradigm that treats computation as the evaluation of mathematical functions and avoids state and mutable data. It emphasizes the application of functions, in contrast to the imperative programming style, which emphasizes changes in state. Functional programming has its roots in the or logic programming Logic programming is, in its broadest sense, the use of mathematical logic for computer programming. In this view of logic programming, which can be traced at least as far back as John McCarthy's advice-taker proposal, logic is used as a purely declarative representation language, and a theorem-prover or model-generator is used as the problem-, use alternative forms of description.
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Definitions
A programming language is a notation for writing programs A computer program is a sequence of instructions written to perform a specified task for a computer. A computer requires programs to function, typically executing the program's instructions in a central processor. The program has an executable form that the computer can use directly to execute the instructions. The same program in its human-, which are specifications of a computation or algorithm.[1] Some, but not all, authors restrict the term "programming language" to those languages that can express all possible algorithms.[1][2] Traits often considered important for what constitutes a programming language include:
- Function and target: A computer programming language is a language[3] used to write computer programs A computer program is a sequence of instructions written to perform a specified task for a computer. A computer requires programs to function, typically executing the program's instructions in a central processor. The program has an executable form that the computer can use directly to execute the instructions. The same program in its human-, which involve a computer A computer is a programmable machine that receives input, stores and manipulates data//information, and provides output in a useful format performing some kind of computation[4] or algorithm In mathematics, computer science, and related subjects, an algorithm is an effective method for solving a problem expressed as a finite sequence of instructions. Algorithms are used for calculation, data processing, and many other fields and possibly control external devices such as printers In computing, a printer is a peripheral which produces a hard copy of documents stored in electronic form, usually on physical print media such as paper or transparencies. Many printers are primarily used as local peripherals, and are attached by a printer cable or, in most newer printers, a USB cable to a computer which serves as a document, disk drives Disk storage or disc storage is a general category of storage mechanisms, in which data are digitally recorded by various electronic, magnetic, optical, or mechanical methods on a surface layer deposited of one or more planar, round and rotating platters. A disk drive is a device implementing such a storage mechanism with fixed or removable media;, robots A robot is an automatically guided machine which is able to do tasks on its own, almost always due to electronically-programmed instructions. Another common characteristic is that by its appearance or movements, a robot often conveys a sense that it has intent or agency of its own,[5] and so on. For example PostScript PostScript is a dynamically typed concatenative programming language created by John Warnock and Charles Geschke in 1982. PostScript is best known for its use as a page description language in the electronic and desktop publishing areas programs are frequently created by another program to control a computer printer or display. More generally, a programming language may describe computation on some, possibly abstract, machine. It is generally accepted that a complete specification for a programming language includes a description, possibly idealized, of a machine or processor for that language.[6] In most practical contexts, a programming language involves a computer; consequently programming languages are usually defined and studied this way.[7] Programming languages differ from natural languages In the philosophy of language, a natural language is any language which arises in an unpremeditated fashion as the result of the innate facility for language possessed by the human intellect. A natural language is typically used for communication, and may be spoken, signed, or written. Natural language is distinguished from constructed languages in that natural languages are only used for interaction between people, while programming languages also allow humans to communicate instructions to machines.
- Abstractions: Programming languages usually contain abstractions The concept originated by analogy with abstraction in mathematics. The mathematical technique of abstraction begins with mathematical definitions; this has the fortunate effect of finessing some of the vexing philosophical issues of abstraction. For example, in both computing and in mathematics, numbers are concepts in the programming languages, for defining and manipulating data structures In computer science, a data structure is a particular way of storing and organizing data in a computer so that it can be used efficiently or controlling the flow of execution In computer science, control flow refers to the order in which the individual statements, instructions, or function calls of an imperative or a declarative program are executed or evaluated. The practical necessity that a programming language support adequate abstractions is expressed by the abstraction principle;[8] this principle is sometimes formulated as recommendation to the programmer to make proper use of such abstractions.[9]
- Expressive power: The theory of computation The theory of computation or computer theory is the branch of computer science and mathematics that deals with whether and how efficiently problems can be solved on a model of computation, using an algorithm. The field is divided into two major branches: computability theory and complexity theory, but both branches deal with formal models of classifies languages by the computations they are capable of expressing. All Turing complete Turing completeness, named after Alan Turing, is significant in that every plausible design for a computing device so far advanced can be emulated by a universal Turing machine — an observation that has become known as the Church-Turing thesis. Thus, a machine that can act as a universal Turing machine can, in principle, perform any calculation languages can implement the same set of algorithms In mathematics, computer science, and related subjects, an algorithm is an effective method for solving a problem expressed as a finite sequence of instructions. Algorithms are used for calculation, data processing, and many other fields. ANSI/ISO SQL SQL , often referred to as Structured Query Language, is a database computer language designed for managing data in relational database management systems (RDBMS), and originally based upon relational algebra. Its scope includes data insert, query, update and delete, schema creation and modification, and data access control. SQL was one of the and Charity Charity is a purely functional experimental programming language, developed at the University of Calgary. Based on ideas by Hagino Tatsuya, it is completely grounded in category theory are examples of languages that are not Turing complete, yet often called programming languages.[10][11]
Markup languages A markup language is a system for annotating a text in a way which is syntactically distinguishable from that text. Examples include revision instructions by editors, traditionally written with a blue pencil on authors' manuscripts, typesetting instructions such those found in troff and LaTeX, and structural markers such as XML tags. Markup is like XML Extensible Markup Language is a set of rules for encoding documents in machine-readable form. It is defined in the XML 1.0 Specification produced by the W3C, and several other related specifications, all gratis open standards, HTML HTML, which stands for HyperText Markup Language, is the predominant markup language for web pages. It is written in the form of HTML elements consisting of "tags" surrounded by angle brackets within the web page content or troff troff is a document processing system developed by AT&T for the Unix operating system, which define structured data A data model in software engineering is an abstract model that describes how data is represented and accessed. Data models formally define data elements and relationships among data elements for a domain of interest, are not generally considered programming languages.[12][13][14] Programming languages may, however, share the syntax with markup languages if a computational semantics is defined. XSLT XSLT is a declarative, XML-based language used for the transformation of XML documents into other XML documents. The original document is not changed; rather, a new document is created based on the content of an existing one. The new document may be serialized (output) by the processor in standard XML syntax or in another format, such as HTML or, for example, is a Turing complete Turing completeness, named after Alan Turing, is significant in that every plausible design for a computing device so far advanced can be emulated by a universal Turing machine — an observation that has become known as the Church-Turing thesis. Thus, a machine that can act as a universal Turing machine can, in principle, perform any calculation XML dialect.[15][16][17] Moreover, LaTeX Latex as found in nature is a milky sap-like fluid found in 10% of all flowering plants . It is a complex emulsion consisting of proteins, alkaloids, starches, sugars, oils, tannins, resins, and gums that coagulates on exposure to air. It is usually exuded after tissue injury. In most plants, latex is white, but some have yellow, orange, or, which is mostly used for structuring documents, also contains a Turing complete subset.[18][19]
The term computer language is sometimes used interchangeably with programming language.[20] However, the usage of both terms varies among authors, including the exact scope of each. One usage describes programming languages as a subset of computer languages.[21] In this vein, languages used in computing that have a different goal than expressing computer programs are generically designated computer languages. For instance, markup languages are sometimes referred to as computer languages to emphasize that they are not meant to be used for programming.[22] Another usage regards programming languages as theoretical constructs for programming abstract machines, and computer languages as the subset thereof that runs on physical computers, which have finite hardware resources.[23] John C. Reynolds John Reynolds studied at Purdue University and then earned a PhD in theoretical physics from Harvard University in 1961. He was Professor of Information science at Syracuse University from 1970 to 1986. Since then he has been Professor of Computer Science at Carnegie Mellon University. He has held visiting positions at Aarhus University , emphasizes that formal specification In computer science, a formal specification is a mathematical description of software or hardware that may be used to develop an implementation. It describes what the system should do, not how the system should do it. Given such a specification, it is possible to use formal verification techniques to demonstrate that a candidate system design is languages are just as much programming languages as are the languages intended for execution. He also argues that textual and even graphical input formats that affect the behavior of a computer are programming languages, despite the fact they are commonly not Turing-complete, and remarks that ignorance of programming language concepts is the reason for many flaws in input formats.[24]
Design and implementation
Programming languages share properties with natural languages related to their purpose as vehicles for communication, having a syntactic form separate from its semantics, and showing language families of related languages branching one from another.[3] But as artificial constructs, they also differ in fundamental ways from languages that have evolved through usage. A significant difference is that a programming language can be fully described and studied in its entirety, since it has a precise and finite definition.[25] By contrast, natural languages have changing meanings given by their users in different communities. While constructed languages A planned or constructed language—known colloquially or informally as a conlang—is a language whose phonology, grammar, and/or vocabulary have been consciously devised by an individual or group, instead of having evolved naturally. There are many possible reasons to create a constructed language: to ease human communication ; to bring fiction are also artificial languages designed from the ground up with a specific purpose, they lack the precise and complete semantic definition that a programming language has.
Many languages have been designed from scratch, altered to meet new needs, combined with other languages, and eventually fallen into disuse. Although there have been attempts to design one "universal" programming language that serves all purposes, all of them have failed to be generally accepted as filling this role.[26] The need for diverse programming languages arises from the diversity of contexts in which languages are used:
- Programs range from tiny scripts written by individual hobbyists to huge systems written by hundreds of programmers A programmer, computer programmer or coder is someone who writes computer software. The term computer programmer can refer to a specialist in one area of computer programming or to a generalist who writes code for many kinds of software. One who practices or professes a formal approach to programming may also be known as a programmer analyst. A.
- Programmers range in expertise from novices who need simplicity above all else, to experts who may be comfortable with considerable complexity.
- Programs must balance speed, size, and simplicity on systems ranging from microcontrollers A microcontroller is a small computer on a single integrated circuit containing a processor core, memory, and programmable input/output peripherals. Program memory in the form of NOR flash or OTP ROM is also often included on chip, as well as a typically small amount of RAM. Microcontrollers are designed for embedded applications, in contrast to to supercomputers A supercomputer is a computer that is at the frontline of current processing capacity, particularly speed of calculation. Supercomputers were introduced in the 1960s and were designed primarily by Seymour Cray at Control Data Corporation , which led the market into the 1970s until Cray left to form his own company, Cray Research. He then took over.
- Programs may be written once and not change for generations, or they may undergo continual modification.
- Finally, programmers may simply differ in their tastes: they may be accustomed to discussing problems and expressing them in a particular language.
One common trend in the development of programming languages has been to add more ability to solve problems using a higher level of abstraction The concept originated by analogy with abstraction in mathematics. The mathematical technique of abstraction begins with mathematical definitions; this has the fortunate effect of finessing some of the vexing philosophical issues of abstraction. For example, in both computing and in mathematics, numbers are concepts in the programming languages,. The earliest programming languages were tied very closely to the underlying hardware of the computer. As new programming languages have developed, features have been added that let programmers express ideas that are more remote from simple translation into underlying hardware instructions. Because programmers are less tied to the complexity of the computer, their programs can do more computing with less effort from the programmer. This lets them write more functionality per time unit.[27]
Natural language processors have been proposed as a way to eliminate the need for a specialized language for programming. However, this goal remains distant and its benefits are open to debate. Edsger W. Dijkstra took the position that the use of a formal language is essential to prevent the introduction of meaningless constructs, and dismissed natural language programming as "foolish".[28] Alan Perlis was similarly dismissive of the idea.[29]
A language's designers and users must construct a number of artifacts that govern and enable the practice of programming. The most important of these artifacts are the language specification and implementation.
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Q. I know that people say that one programming language is faster than another and that C is a really fast programming language but is there an actual unit in which the speed of programming languages are measured? Like the number of lines executed per second on a computer that has a speed of one GHz or something?
Asked by Jenn - Thu Jun 17 16:35:51 2010 - - 2 Answers - 0 Comments
A. Typically you'll take a particular test... Like sorting a million integers or doing some sort of a physics calculation or difficult mathematical operation. Pick something that'll take a decent amount of time to run - say a minute or two. Then, you code up the test in a bunch of different languages (typically in a straight forward manner, not doing any fancy tricks) and see how long they each take. Obviously different algorithms and stuff will have different results, as each different language has strong and weak sections. The reason a language like C or C++ are considered very fast is because they are compiled, so when you are running the program you are running in the native language of the computer (machine code). This is different… [cont.]
Answered by Bill C - Thu Jun 17 16:59:51 2010
