A programming language in common though decreasing use. Pascal was designed as a tool to assist the teaching of programming as a systematic discipline. To that end it incorporates the control structures of structured programming—sequence, selection, and repetition—and data structures—arrays, records, files, sets, and user-defined types. It is an austere language, with a minimum of facilities, but what is provided is so well suited to its task that the language is in practice more powerful than its more elaborate competitors.

Pascal was relatively easy to implement on a variety of machines since the Pascal compiler was written in Pascal. Used first as an educational tool, Pascal became a more-or-less standard language for the teaching of computer science. It spread into microcomputing in the form of the UCSD p-System, but only achieved widespread popularity with Turbo Pascal. In 1982 ISO Standard Pascal was defined, but modern compilers, especially those for microcomputers, implement an extended and nonstandard version of the language.

http://www.pascal-central.com/docs/iso7185.pdf The Pascal standard (1990 revision)