Chapter 1 : Software and software engineering

Chapter 1 : Software and software engineering

He had the classic look of a senior executive for a major software company—mid-40s, slightly graying at the temples, trim and athletic, with eyes that penetrated the listener as he spoke. But what he said shocked me. “Software is dead.” I blinked with surprise and then smiled. “You’re joking, right? The world is driven by software and your company has profited handsomely because of it. It isn’t dead! It’s alive and growing.” He shook his head emphatically. “No, it’s dead . . . at least as we once knew it.” I leaned forward. “Go on.” He spoke while tapping the table for emphasis. “The old-school view of software—you buy it, you own it, and it’s your job to manage it—that’s coming to an end. Today, with Web 2.0 and pervasive computing coming on strong, we’re going to be seeing a completely different generation of software. It’ll be delivered via the Internet and will look exactly like it’s residing on each user’s computing device . . . but it’ll reside on a far-away server.”

QUICK LOOK

What is it? 

Computer software is the product that software professionals build and then support over the long term. It encompasses programs that execute within a computer of any size and architecture, content that is presented as the computer programs execute, and descriptive information in both hard copy and virtual forms that encompass virtually any electronic media. Software engineering encompasses a process, a collection of methods (practice) and an array of tools that allow professionals to build highquality computer software. 

Who does it? 

Software engineers build and support software, and virtually everyone in the industrialized world uses it either directly or indirectly. Why is it important? Software is important because it affects nearly every aspect of our lives and has become pervasive in our commerce, our culture, and our everyday activities.Software engineering is important because it enables us to build complex systems in a timely manner and with high quality. 

What are the steps? 

You build computer software like you build any successful product, by applying an agile, adaptable process that leads to a high-quality result that meets the needs of the people who will use the product. You apply a software engineering approach. 

What is the work product? 

From the point of view of a software engineer, the work product is the set of programs, content (data), and other work products that are computer software. But from the user’s viewpoint, the work product is the resultant information that somehow makes the user’s world better. 

How do I ensure that I’ve done it right? 

Read the remainder of this book, select those ideas that are applicable to the software that you build, and apply them to your work.

I had to agree. “So, your life will be much simpler. You guys won’t have to worry about five different versions of the same App in use across tens of thousands of users.” He smiled. “Absolutely. Only the most current version residing on our servers. When we make a change or a correction, we supply updated functionality and content to every user. Everyone has it instantly!” I grimaced. “But if you make a mistake, everyone has that instantly as well.” He chuckled. “True, that’s why we’re redoubling our efforts to do even better software engineering. Problem is, we have to do it ‘fast’ because the market has accelerated in every application area.” I leaned back and put my hands behind my head. “You know what they say, . . . you can have it fast, you can have it right, or you can have it cheap. Pick two!” “I’ll take it fast and right,” he said as he began to get up. I stood as well. “Then you really do need software engineering.” “I know that,” he said as he began to move away. “The problem is, we’ve got to convince still another generation of techies that it’s true!”

Is software really dead? If it was, you wouldn’t be reading this book! Computer software continues to be the single most important technology on the world stage. And it’s also a prime example of the law of unintended consequences. Fifty years ago no one could have predicted that software would become an indispensable technology for business, science, and engineering; that software would enable the creation of new technologies (e.g., genetic engineering and nanotechnology), the extension of existing technologies (e.g., telecommunications), and the radical change in older technologies (e.g., the printing industry); that software would be the driving force behind the personal computer revolution; that shrink-wrapped software products would be purchased by consumers in neighborhood malls; that software would slowly evolve from a product to a service as “on-demand” software companies deliver just-in-time functionality via a Web browser; that a software company would become larger and more influential than almost all industrial-era companies; that a vast software-driven network called the Internet would evolve and change everything from library research to consumer shopping to political discourse to the dating habits of young (and not so young) adults. No one could foresee that software would become embedded in systems of all kinds: transportation, medical, telecommunications, military, industrial, entertainment, office machines, . . . the list is almost endless. And if you believe the law of unintended consequences, there are many effects that we cannot yet predict. No one could predict that millions of computer programs would have to be corrected, adapted, and enhanced as time passed. The burden of performing these “maintenance” activities would absorb more people and more resources than all work applied to the creation of new software. As software’s importance has grown, the software community has continually attempted to develop technologies that will make it easier, faster, and less expensive