A programming language is an artificial language that can be used to create programs which control the behavior of a machine, particularly a computer.[1] Programming languages are defined by syntactic and semantic rules which describe their structure and meaning respectively. Programming languages are also used to facilitate communication about the task of organizing and manipulating information, and to express algorithms precisely.
Many programming languages have some form of written specification of their syntax and semantics; some are defined by a specification document (for example, an ISO Standard), while others have a dominant implementation (such as Perl).
Definitions
Traits often considered important for constituting a programming language:
Function: A programming language is a language used to write computer programs, which involve a computer performing some kind of computation[2] or algorithm and possibly control external devices such as printers, robots,[3] and so on.
Target: Programming languages differ from natural languages in that natural languages are only used for interaction between people, while programming languages also allow humans to communicate instructions to machines. Some programming languages are used by one device to control another. For example PostScript programs are frequently created by another program to control a computer printer or display.
Constructs: Programming languages may contain constructs for defining and manipulating data structures or controlling the flow of execution.
Expressive power: The theory of computation classifies languages by the computations they are capable of expressing. All Turing complete languages can implement the same set of algorithms. ANSI/ISO SQL and Charity are examples of languages that are not Turing complete yet often called programming languages.[4][5]
Some authors restrict the term "programming language" to those languages that can express all possible algorithms;[6] sometimes the term "computer language" is used for more limited artificial languages.
Non-computational languages, such as markup languages like HTML or formal grammars like BNF, are usually not considered programming languages. A programming language (which may or may not be Turing complete) may be embedded in these non-computational (host) languages.
Many programming languages have some form of written specification of their syntax and semantics; some are defined by a specification document (for example, an ISO Standard), while others have a dominant implementation (such as Perl).
Definitions
Traits often considered important for constituting a programming language:
Function: A programming language is a language used to write computer programs, which involve a computer performing some kind of computation[2] or algorithm and possibly control external devices such as printers, robots,[3] and so on.
Target: Programming languages differ from natural languages in that natural languages are only used for interaction between people, while programming languages also allow humans to communicate instructions to machines. Some programming languages are used by one device to control another. For example PostScript programs are frequently created by another program to control a computer printer or display.
Constructs: Programming languages may contain constructs for defining and manipulating data structures or controlling the flow of execution.
Expressive power: The theory of computation classifies languages by the computations they are capable of expressing. All Turing complete languages can implement the same set of algorithms. ANSI/ISO SQL and Charity are examples of languages that are not Turing complete yet often called programming languages.[4][5]
Some authors restrict the term "programming language" to those languages that can express all possible algorithms;[6] sometimes the term "computer language" is used for more limited artificial languages.
Non-computational languages, such as markup languages like HTML or formal grammars like BNF, are usually not considered programming languages. A programming language (which may or may not be Turing complete) may be embedded in these non-computational (host) languages.
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