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ALGOL (short for ALGOrithmic Language)〔The name of the family is sometimes given in mixed case ((''Algol 60'' )), and sometimes in all uppercase ((''ALGOL68'' )). For simplicity this article uses ''ALGOL''.〕 is a family of imperative computer programming languages, originally developed in the mid-1950s, which greatly influenced many other languages and was the standard method for algorithm description used by the ACM in textbooks and academic sources for more than thirty years.〔(''Collected Algorithms of the ACM'' ) Compressed archives of the algorithms. ACM.〕 In the sense that most modern languages are "algol-like", it was arguably the most successful of the four high-level programming languages with which it was roughly contemporary: Fortran, Lisp, and COBOL. It was designed to avoid some of the perceived problems with FORTRAN and eventually gave rise to many other programming languages, including BCPL, B, Pascal, PL/I, Simula, and C. ALGOL introduced code blocks and the begin…end pairs for delimiting them. It was also the first language implementing nested function definitions with lexical scope. Moreover, it was the first programming language which gave detailed attention to formal language definition and through the ''Algol 60 Report'' introduced Backus–Naur Form, a principal notation for language design.There were three major specifications: * ALGOL 58 – originally proposed to be called IAL (for International Algebraic Language). * ALGOL 60 – first implemented as ''X1 ALGOL 60'' in mid-1960 – revised 1963 * ALGOL 68 – revised 1973〔(【引用サイトリンク】year=1973 )〕 – introduced new elements including flexible arrays, slices, parallelism, operator identification, and various extensibility features. Niklaus Wirth based his own ALGOL W on ALGOL 60 before developing Pascal. Algol-W (for the IBM 360) was based on the proposal for the next generation ALGOL, but the ALGOL 68 committee decided on a design that was more complex and advanced, rather than a cleaned, simplified ALGOL 60. The official ALGOL versions are named after the year they were first published. Algol 68 is substantially different from Algol 60 and was not well received, so that in general "Algol" means Algol 60 and dialects thereof. Fragments of ALGOL-like syntax are sometimes still used as pseudocode. ==Important implementations== The International Algebraic Language (IAL) was extremely influential and generally considered the ancestor of most of the modern programming languages (the so-called Algol-like languages). Additionally, in computer science, ALGOL object code was a simple and compact and stack-based instruction set architecture mainly used in teaching compiler construction and other high order languages (of which Algol is generally considered the first). 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「ALGOL」の詳細全文を読む スポンサード リンク
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