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A programming paradigm is a fundamental style of computer programming, serving as a way of building the structure and elements of computer programs. Capabilities and styles of various programming languages are defined by their supported programming paradigms; some programming languages are designed to follow only one paradigm, while others support multiple paradigms. Programming paradigms that are often distinguished include imperative, declarative, functional, object-oriented, procedural, logic and symbolic programming.〔Nørmark, Kurt. ''(Overview of the four main programming paradigms )''. Aalborg University, 9 May 2011. Retrieved 22 September 2012.〕 With different paradigms, programs can be seen and built in different ways; for example, in object-oriented programming, a program is a collection of objects interacting in explicitly defined ways, while in declarative programming the computer is told only what the problem is, not how to actually solve it. == Overview == Just as software engineering (as a process) is defined by differing ''methodologies'', so the programming languages (as models of computation) are defined by differing ''paradigms''. Some languages are designed to support one particular paradigm (Smalltalk supports object-oriented programming, Haskell supports functional programming), while other programming languages support multiple paradigms (such as Object Pascal, C++, Java, C#, Scala, Visual Basic, Common Lisp, Scheme, Perl, Python, Ruby, Oz and F#). For example, programs written in C++ or Object Pascal can be purely procedural, purely object-oriented, or they can contain elements of both or other paradigms. Software designers and programmers decide how to use those paradigm elements. In object-oriented programming, programmers can think of a program as a collection of interacting objects, while in functional programming a program can be thought of as a sequence of stateless function evaluations. When programming computers or systems with many processors, process-oriented programming allows programmers to think about applications as sets of concurrent processes acting upon logically shared data structures. Many programming paradigms are as well known for what techniques they ''forbid'' as for what they enable. For instance, pure functional programming disallows the use of side-effects, while structured programming disallows the use of the goto statement. Partly for this reason, new paradigms are often regarded as doctrinaire or overly rigid by those accustomed to earlier styles. Avoiding certain techniques can, though, make it easier to prove theorems about the correctness of a program, or simply to understand its behavior. Programming paradigms can also be compared with ''programming models'' that are abstractions of computer systems. For example, the "von Neumann model" is a programming model used in traditional sequential computers. For parallel computing, there are many possible models typically reflecting different ways processors can be interconnected. The most common are based on shared memory, distributed memory with message passing, or a hybrid of the two. Some programming language researchers criticise the notion of paradigms as a classification of programming languages, e.g. Krishnamurthi.〔.〕 They argue that many programming languages cannot be strictly classified into one paradigm, but rather include features from several paradigms. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「programming paradigm」の詳細全文を読む スポンサード リンク
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