Evolution of Software Engineering

Any application on computer runs through software. As computer technologies have changed tremendously in the last five decades, accordingly, the software development has undergone significant changes in the last few decades of 20th century. In the early years, the software size used to be small and those were developed either by a single programmer or by a small programming team. The program development was dependent on the programmer’s skills and no strategic software practices were present. In the early 1980s, the size of software and the application domain of software increased. Consequently, its complexity has also increased. Bigger teams were engaged in the development of Software. The software development became more bit organized and software development management practices came into existence.

In this period, higher order programming languages like PASCAL and COBOL came into existence. The use of these made programming much easier. In this decade, some structural design practices like top down approach were introduced. The concept of quality assurance was also introduced. However, the business aspects like cost estimation, time estimation etc. of software were in their elementary stages.

In the late 1980s and 1990s, software development underwent revolutionary changes. Instead of a programming team in an organization, full-fledged software companies evolved (called software houses). A software houses primary business is to produce software. As software house may offer a range of services, including hiring out of suitably qualified personnel to work within client’s team, consultancy and a complete system design and development service. The output of these companies was ‘Software’. Thus, they viewed the software as a product and its functionality as a process. The concept of software engineering was introduced and Software became more strategic, disciplined and commercial. As the developer of Software and user of Software became separate organization, business concepts like software costing, Software quality, laying of well-defined requirements, Software reliability, etc., came into existence. In this phase an entirely new computing environments based on a knowledge-based systems get created. Moreover, a powerful new concept of object-oriented programming was also introduced.

The production of software became much commercial. The software development tools were devised. The concept of Computer Aided Software Engineering (CASE) tools came into existence. The software development became faster with the help of CASE tools.

The latest trend in software engineering includes the concepts of software reliability, reusability, scalability etc. More and more importance is now given to the quality of the software product. Just as automobile companies try to develop good quality automobiles, software companies try to develop good quality Software. The software creates the most valuable product of the present era, i.e., information.

The following Table summarizes the evolution of software:

1960s Infancy	Machine Code
1970s Project Years	Higher Order Languages
1980s Project Years	Project Development
1990s Process and Production Era	Software Reuse