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In computer science, a high-level programming language is a programming language with strong abstraction from the details of the computer. In comparison to low-level programming languages, it may use natural language elements, be easier to use, or may automate (or even hide entirely) significant areas of computing systems (e.g. memory management), making the process of developing a program simpler and more understandable relative to a lower-level language. The amount of abstraction provided defines how "high-level" a programming language is.〔(HThreads - RD Glossary )〕 In the 1960s, high-level programming languages using a compiler were commonly called autocodes.〔〕 Examples of autocodes are COBOL and Fortran.〔〕 The first high-level programming language designed for computers was Plankalkül, created by Konrad Zuse.〔Giloi, Wolfgang, K. (1997). "Konrad Zuse's Plankalkül: The First High-Level "non von Neumann" Programming Language". IEEE Annals of the History of Computing, vol. 19, no. 2, pp. 17–24, April–June, 1997. ((abstract) )〕 However, it was not implemented in his time, and his original contributions were (due to World War II) largely isolated from other developments, although it influenced Heinz Rutishauser's language "Superplan" (and to some degree also Algol). The first really widespread high-level language was Fortran, a machine independent development of IBM's earlier Autocode systems. Algol, defined in 1958 and 1960, by committees of European and American computer scientists, introduced recursion as well as nested functions under lexical scope. It was also the first language with a clear distinction between value and name-parameters and their corresponding semantics.〔Although it lacked a notion of reference-parameters, which could be a problem in some situations. Several successors, including AlgolW, Algol68, Simula, Pascal, Modula and Ada therefore included reference-parameters (The related C-language family instead allowed addresses as value-parameters).〕 Algol also introduced several structured programming concepts, such as the while-do and if-then-else constructs and its syntax was the first to be described by a formal method, Backus–Naur Form (BNF). During roughly the same period Cobol introduced records (also called structs) and Lisp introduced a fully general lambda abstraction in a programming language for the first time. == Features == "High-level language" refers to the higher level of abstraction from machine language. Rather than dealing with registers, memory addresses and call stacks, high-level languages deal with variables, arrays, objects, complex arithmetic or boolean expressions, subroutines and functions, loops, threads, locks, and other abstract computer science concepts, with a focus on usability over optimal program efficiency. Unlike low-level assembly languages, high-level languages have few, if any, language elements that translate directly into a machine's native opcodes. Other features, such as string handling routines, object-oriented language features, and file input/output, may also be present. 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「High-level programming language」の詳細全文を読む スポンサード リンク
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