No abstract available.

Abstract The study presents the results of an experiment on programmers' descriptions and understanding. The 12 participants, students of computing, have produced notes on Turing's description of his universal machine and, in a second experiment phase, have made mutual evaluations of their notes. The analysis of the resulting notes shows large individual differences of styles and evaluations with respect to all significant issues of the descriptions and understanding, including the evaluations of program descriptions having particularly full formal characteristics. The consequences of the observations for the teaching of programming and for programming methodologies are discussed. The Appendix gives an annotated version of Turing's description of the universal machine.

Received December 1978.

Some social aspects of programming are illuminated through analogies with similar aspects of mathematics and natural languages. The split between pure and applied mathematics is found similarly in programming. The development of natural languages toward flexionless, word-order based language types speaks for programming language design based on general, abstract constructs. By analogy with incidents of the history of artificial, auxiliary languages it is suggested that Fortran and Cobol will remain dominant for a long time to come. The most promising avenues for further work of wide influence is seen to be high quality program literature (i.e. programs) of general utility and studies of questions related to program style.

The report gives a complete defining description of the international algorithmic language ALGOL 60. This is a language suitable for expressing a large class of numerical processes in a form sufficiently concise for direct automatic translation into the language of programmed automatic computers. The introduction contains an account of the preparatory work leading up to the final conference, where the language was defined. In addition the notions reference language, publication language, and hardware representations are explained. In the first chapter a survey of the basic constituents and features of the language is given, and the formal notation, by which the syntactic structure is defined, is explained. The second chapter lists all the basic symbols, and the syntactic units know as identifiers, numbers, and strings are defined. Further, some important notions such as quantity and value are defined. The third chapter explains the rules for forming expressions, and the means of these expressions. Three different types of expressions exist: arithmetic, Boolean (logical), and designational. The fourth chapter describes the operational units of the language, known and statements. The basic statements are: assignment statements (evaluation of a formula), go to statements (explicit break of the sequence of execution of statements), dummy statements, and procedure statements (call for execution of a closed process, defined by a procedure declaration). The formation of more complex structures, having statement character, is explained. Thes include: conditional statements, for statements, compound statements, and blocks. In the fifth chapter the units known as declarations, serving for defining permanent properties of the units entering into a process described in the language, are defined. The report ends with two detailed examples of the use of the language, and an alphabetic index of definitions.

This paper gives a brief review of the design of the machine GIER (42-bit words, 1-k core store, 12-k drum store, 50-microsecond fixed point, 100-microsecond floating, add time) and its programming systems. The principal subjects are: The order structure, the operating system, the ALGOL 60 system, an evaluation of the order structure, the hardware organization, and the latest hardware extensions, including a hybrid computer system.