Let’s look at some of the definitions of software engineering.
Software Engineering as defined by IEEE (International institute of Electric and Electronic Engineering). IEEE is an authentic institution regarding the computer related issues.
“The application of a systematic, disciplined, quantifiable approach to the development, operation, and maintenance of software; that is, the application of engineering to software.”
Before explaining this definition lets first look at another definition of Software Engineering given by Ian Somerville.
“All aspects of software production’ Software engineering is not just concerned with the technical processes of software development but also with activities such as software project management and with the development of tools, methods and theories to support software production”.
These definitions make it clear that Software Engineering is not just about writing code.
Software Engineering is the set of processes and tools to develop software. Software Engineering is the combination of all the tools, techniques, and processes that used in software production. Therefore Software Engineering encompasses all those things that are used in software production like:
- Programming Language
- Programming Language Design
- Software Design Techniques
- Development etc.
So all those thing that are related to software are also related to software engineering. Some of you might have thought that how programming language design could be related to software engineering. If you look more closely at the software engineering
Definitions described above then you will definitely see that software engineering is related to all those things that are helpful in software development. So is the case with programming language design. Programming language design is one of the major successes in last fifty years. The design of Ada language was considered as the considerable effort in software engineering.
These days object-oriented programming is widely being used. If programming languages will not support object-orientation then it will be very difficult to implement object-oriented design using object-oriented principles. All these efforts made the basis of software engineering.
Let’s talk something about what is well-engineered software. Well-engineered software is one that has the following characteristics.
- It is reliable
- It has good user-interface
- It has acceptable performance
- It is of good quality
- It is cost-effective
Every company can build software with unlimited resources but well-engineered software is one that conforms to all characteristics listed above. Software has very close relationship with economics. Whenever we talk about engineering systems we always first analyze whether this is economically feasible or not. Therefore you have to engineer all the activities of software development while keeping its economic feasibility intact.
Challenges for a software engineer
The major challenges for a software engineer is that he has to build software within limited time and budget in a cost-effective way and with good quality
Therefore well-engineered software has the following characteristics.
- Provides the required functionality
But most of the times software engineers ends up in conflict among all these goals. It is also a big challenge for a software engineer to resolve all these conflicts.
The Balancing Act!
Software Engineering is actually the balancing act. You have to balance many things like cost, user friendliness, Efficiency, Reliability etc. You have to analyze which one is the more important feature for your software is it reliability, efficiency, user friendliness or something else. There is always a trade-off among all these requirements of software. It may be the case that if you try to make it more user-friendly then the efficiency may suffer. And if you try to make it more cost-effective then reliability may suffer. Therefore there is always a trade-off between these characteristics of software.
These requirements may be conflicting. For example, there may be tension among the following:
- Cost vs. Efficiency
- Cost vs. Reliability
- Efficiency vs. User-interface
A Software engineer is required to analyze these conflicting entities and tries to strike a balance.
Challenge is to balance these requirements. Software Engineers always confront with the challenge to make a good balance of all these things depending on the requirements of the particular software system at hand.
He should analyze how much weight should all these things get such that it will have acceptable quality, acceptable performance and will have acceptable user-interface.
In some software the efficiency is more important and desirable. For example if we talk about a cruise missile or a nuclear reactor controller that are droved by the software systems then performance and reliability is far more important than the cost-effectiveness and user-friendliness. In these cases if your software does not react within a certain amount of time then it may result in the disaster like Chernobyl accident.
Therefore software development is a process of balancing among different characteristics of software described in the previous section. And it is an art to come up with such a good balance and that art can be learned from experience.