The document discusses software engineering and defines software as instructions, data structures, and documents that provide desired functions when executed on a computer. It notes that software is engineered rather than physical, does not wear out in the way hardware does, and is complex and custom-built for specific uses. The document also outlines different types of software applications and common myths about software development.

1. 1
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are
provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
Chapter 1
The Product

2. 2
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are
provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
What is Software?
1) instructions (programs) that when
executed provide desired function and
performance
2) data structures that enable the programs to
adequately manipulate information
3) documents that describe the operation and
use of the programs
A logical rather than physical system element

3. 3
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are
provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
What is Software?
software is engineered
software doesn’t wear out
software is custom built
software is complex

4. 4
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are
provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
Failure (“Bathtub”) Curve for Hardware
Time
Failure
Rate
Infant
mortality
Wear
out

5. 5
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are
provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
Wear vs. Deterioration

6. 6
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are
provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
Software Applications
system software
real-time software
business software
engineering/scientific software
embedded software
PC software
WebApps (Web applications)
 AI software

7. 7
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are
provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
Software Myths
 Management
 We have standards
 We have new computers
 We’ll add more people to catch up
 I outsourced it, I’m done
 Customer
 We have general objectives, let’s start
 Change is easily accommodated
 Practitioner
 We’ll write it and be done
 I can’t assess quality until it is running
 I only need deliver code
 Software engineering is about meaningless documents

8. 8
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are
provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
The Cost of Change

9. 9
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are
provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
Software Poses Challenges
How do we ensure the quality of the software that
we produce?
How do we meet growing demand and still
maintain budget control?
How do we upgrade an aging "software plant?"
How do we avoid disastrous time delays?
How do we successfully institute new software
technologies?