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Chapter 6 • agile Modeling and prototyping 151

Prototyping
As a systems analyst presenting a prototype of an information system, you are keenly interested
in the reactions of users and management to the prototype. You want to know in detail how they
react to working with the prototype and how good the fit is between their needs and the proto-
typed features of the system. You gather reactions through observation, interviews, and feedback
sheets (possibly questionnaires) designed to elicit each person’s opinion about the prototype as
he or she interacts with it.
Information gathered in the prototyping phase allows an analyst to set priorities and redi-
rect plans inexpensively, with minimal disruption. Therefore, prototyping and planning go
hand-in-hand.

Kinds of Prototypes
The word prototype is used in many different ways. Rather than attempt to synthesize all these
uses into one definition or try to mandate one correct approach to the somewhat controversial
topic of prototyping, we illustrate how each of several conceptions of prototyping may be use-
fully applied in a particular situation, as shown in Figure 6.1.
PATCHED-UP PROTOTYPE. The first kind of prototyping has to do with constructing a system
that works but is patched up or patched together. In engineering, this approach is referred to
as breadboarding: creating a patched-together, working model of an (otherwise microscopic)
integrated circuit.
An example in information systems is a working model that has all the necessary features
but is inefficient. In this instance of prototyping, users can interact with the system, getting
accustomed to the interface and types of output available. The retrieval and storage of informa-
tion may be inefficient, however, because programs were written rapidly, with the objective of
being workable rather than efficient.

Figure 6.1
Four kinds of prototypes.

Input Process Output

Patched-Up Prototype Nonoperational Prototype

Facility 3
Facility 2
Facility 1
Feature 1

Feature 3

Feature 5

First-of-a-Series Prototype Selected Features Prototype