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Software Engineering: A Practitioner's Approach

Copyright © 1996, 2001 R.S. Pressman & Associates, Inc. For University Use Only May be reproduced ONLY for student use at the university level When used in conjunction with Software Engineering: A Practitioner's Approach. Any other reproduction or use is expressly prohibited.

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1

The Product
CHAPTER OVERVIEW AND COMMENTS The goal of this chapter is to introduce the notion of software as a product designed and built by software engineers. Software is important because it is used by a great many people in society. Software engineers have a moral and ethical responsibility to ensure that the software they design does no serious harm to any people. Software engineers tend to be concerned with the technical elegance of their software products. Customers tend to be concerned only with whether or not a software product meets their needs and is easy to use. 1.1 The Evolving Role of Software The main point of this section is that the primary purpose of software is that of information transformer. Software is used to produce, manage, acquire, modify, display, and transmit information anywhere in the world. The days of the lone programmer are gone. Modern software is developed by teams of software specialists. Yet, the software developer's concerns have remained the same. Why does software take so long to complete? Why does it cost so much to produce? Why can't all errors be found and removed before software is delivered to the customer? 1.2 Software Software is not like the artifacts produced in most other engineering disciplines. Software is developed it is not manufactured in the classical sense. Building a software product is more like constructing a design prototype. Opportunities for replication without customization are not very common. Software may become deteriorate, but it does not wear out. The chief reason for software deterioration is that many changes are made to a software product over its