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organization, the processes performed on the data, and how data are stored
(Romney & Steinbart 2006, p. 62). It is also defined as a graphic representation of
a
system that
uses
a
small
number of
symbol
shapes
to
illustrate
how data
flows
through interconnected processes (McLeod & Schell 2001, p. 401).
2.6.2
Elements of DFD
Romney and Steinbart
(2006, p.
63) state that
a
DFD
is composed of four
basic
elements, as depicted in Figure 2.3:
• Data Sources and Destinations.
A source or destination symbol on the DFD represents an organization or
individual that sends or receives data that the system uses or produces.
• Data Flows.
A
data flow represents the flow of data between processes, data stores, and data
sources and destinations.
• Transformation Processes.
This represents the transformation of data.
• Data Stores.
A
data store is a temporary or permanent repository of data.
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