During the first 5 decades of the age of computing, thousands of programming languages were invented. Many of them followed the path of evolution, following the trends sent by their predecessors. The late 1950s were a revolutionary period in the development of computer programming. The access of electrical engineers to large computers, which became available to research institutions and universities, emerged the rise of a new profession. This Pioneering Era of programming took place from 1955 to 1965. As the demand for programs and programmers grow with the expanse of computing capacity, the tasks became more complex, so a new stage of the development of programming was established – the Stabilizing Era, which lasted from 1965 to 1980.
The beginnings of the Stabilizing Era were marked with the Notes on Structured Programming, written by the Dutch computer scientist E. W. Dijkstra. In these notes, Dijkstra distinguished programming as a discipline. The ideas of Sir Charles Antony Richard Hoare, published in Notes on Structured Programming, influenced the development of innovative programming languages, Pascal being the most notable one. Harlan D. Mills was another influential figure in this era, due to the intensive training courses on structured programming he organized in IBM.
The launch that signaled the beginnings of the Stabilizing Era of programming was the largest software project to date – the IBM System/360, a mainframe computer system family that was developed between 1965 and 1978. This system enabled programmers to start inventing new software instead of rewriting the old, since new computers were no longer introduced every year or two, and they did not render the existing ones obsolete. The S/360 machine offered both decimal and binary arithmetic, and combined business and scientific applications. Thus, the organizational separation between business and scientific programmers was diminished.
The Stabilizing Era turned software into a corporate asset, resulting in huge increase in its values. Some of the major programming languages that were invented in this period include: Simula (introduced in the late 1960s), C (developed between 1969 and 1973), Pascal (1970), Prolog (1972), ML (1973), Smalltalk (mid-70s), and SQL (1978). Most modern programming languages are based on at least one of these ancestors.
This important era of programming teaches us that computer science is a methodological subject in its essence. The programs are being developed for years with the purpose to be generally beneficial for various applications. The first major languages, which were developed with a single purpose, were replaced with multi-purpose languages that had immense capacity to grow and inspire the development of other languages.