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The purpose of this paper is to indicate something of the nature of "good programming." In this context, programming is taken to mean the entire process of communication between humans and computers. The programming process is sub- divided into nine tasks, and an elementary discussion of each of these tasks is presented. Although the paper is primarily directed to the student or novice programmer, more experienced people may find it a worthwhile aid in codifying or reinforcing their experience. [ABSTRACT FROM AUTHOR]

Time and time again software projects, though undertaken by people of considerable intellectual ability, fail. This will doubtless be a continuing phenomenon, because software production is indeed a difficult task requiring wide-ranging skills. Certainly, no single paper can suddenly solve all the problems of software writing and eliminate the failures. The scope of this paper is limited to four stages in the execution of software projects, namely the planning, coding, testing, and final usage. These four crucial areas contain pitfalls that have been responsible for a large proportion of software failures, and it is hoped this paper will help avoid some of them. [ABSTRACT FROM AUTHOR]

The concept of "process" has come to play a central role in many efforts to master the complexity of large computer systems. The purpose of this paper is to discuss useful methods of structuring complex processes, and to relate these to the problems of improving the quality of large computer systems. Two distinct ways of structuring systems are presented, namely, process combination, and process abstraction; these are then used to discuss such topics as concurrency, synchronization, multiprogramming, interpreters, and programmable processors. This discussion is based on a set of precise definitions for such concepts as "process," "processor," "computation," "combination," and "abstraction." The paper relates these definitions to both current research and practical applications, with particular concern for the problems of the performance, reliability, and modifiability of computer systems. [ABSTRACT FROM AUTHOR]

The article presents an overview of papers presented in the December 1974 issue of the periodical "acm computing surveys." All papers selected for publication in this issue cover a range of viewpoints about good programming. There is no fixed set of rules according to which clear, understandable and provable programs can be constructed. There are guidelines ofcourse but the individual programmer's style, his clarity of thought and creativity contribute significantly to the outcome. The first two papers in the issue deal with the relationship between better programming and environment.

New direction in Artificial Intelligence research have led to the need for certain novel features to be embedded in programming languages. This paper gives an overview of the nature of these features, and their implementation in four principal families of AI languages: SAIL; PLANNER/CONNIVER; QLISP/INTERLISP; AND POPLER/POP-2. The programming features described include: new data types and accessing mechanisms for stored expressions; more flexible control structures, including multiple processes and backtracking; pattern matching to allow comparison of data item with a template, and extraction of labeled subexpressions; and deductive mechanisms which allow the programming system to carry out certain activities including modifying the data base and deciding which subroutines to run next using only constraints and guidelines set up by the programmer. [ABSTRACT FROM AUTHOR]

This paper describes the evolution of language features for multiprogramming from event queues and semaphores to critical regions and monitors. It suggests that the choice of language concepts should be guided by two simple principles: First, it should be possible to understand a concurrent program in time- independent terms by an effort proportional to its size; secondly, it should be possible to state assumptions about invariant relationships among program components and have these assumptions checked automatically. The central problems of multiprogramming are illustrated by annotated algorithms written in a well-structured programming language. [ABSTRACT FROM AUTHOR]

The automatic control of a string of high-speed, densely-packed vehicles is studied in a unified approach. Various input structures for the control schemes and their stability are studied and compared. The optimal decentralized regulation theory developed in a previous paper is applied to seek the best feedback control gains for various input structures. Value of information is defined to evaluate the relative merit of these inputs. The results can be easily applied for on-board computer designs in developing new transportation technology such as `personal rapid transit' systems. [ABSTRACT FROM AUTHOR]

The bibliography appearing at the end of this article lists 37 sorting algorithms and 100 books and papers on sorting published in the last 20 years. The basic ideas presented here have been abstracted from this body of work, and the best algorithms known are given as examples. As the algorithms are explained, references to related algorithms and mathematical or experimental analyses are given. Suggestions are then made for choosing the algorithm best suited to a given situation. [ABSTRACT FROM AUTHOR]