Sommerville - Software Engineering

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Progress in software engineering over the last 50 years has been astonishing. Oursocieties could not function without large professional software systems. Nationalutilities and infrastructureenergy, communications and transportall rely oncomplex and mostly reliable computer systems. Software has allowed us to explorespace and to create the World Wide Webthe most significant information systemin the history of mankind. Smartphones and tablets are ubiquitous and an entire appsindustry developing software for these devices has emerged in the past few years.

Humanity is now facing a demanding set of challengesclimate change andextreme weather, declining natural resources, an increasing world population to be fedand housed, international terrorism, and the need to help elderly people lead satisfyingand fulfilled lives. We need new technologies to help us address these challenges and,for sure, software will have a central role in these technologies. Software engineeringis, therefore, critically important for our future on this planet. We have to continue toeducate software engineers and develop the discipline so that we meet the demand formore software and create the increasingly complex future systems that we need.

Of course, there are still problems with software projects. Systems are still sometimes delivered late and cost more than expected. We are creating increasingly complex software systems of systems and we should not be surprised that we encounter difficulties along the way. However, we should not let these problems conceal the real successes in software engineering and the impressive software engineeringmethods and technologies that have been developed.

1.I write about software engineering as it is practiced in industry, without taking an evangelical position on particular approaches such as agile development or formal methods. In reality, industry mixes techniques such as agile and planbased development and this is reflected in the book.

2.I write about what I know and understand. I have had many suggestions foradditional topics that might be covered in more detail such as open sourcedevelopment, the use of the UML and mobile software engineering. But I dont really know enough about these areas. My own work has been in system dependability and in systems engineering and this is reflected in my selection ofadvanced topics for the book.

I believe that the key issues for modern software engineering are managing complexity, integrating agility with other methods and ensuring that our systems aresecure and resilient. These issues have been the driver for the changes and additions in this new edition of my book.

Ihaveextensivelyupdatedthechapteronagilesoftwareengineering,withnewmaterial on Scrum. I have updated other chapters as required to reflect the increasing use of agile methods of software engineering.

Newsupplementarymaterialhasbeenaddedtothewebsite,includingasetofsupporting videos. I have explained key topics on video and recommended related YouTube videos.

1.In Part 1, Introduction to software engineering, I have completely rewrittenChapter 3 (agile methods) and updated this to reflect the increasing use of Scrum.A new case study on a digital learning environment has been added to Chapter 1and is used in a number of chapters. Legacy systems are covered in more detailin Chapter 9. Minor changes and updates have been made to all other chapters.