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THE LAWS OF SOFTWARE PROCESS
Most systems modeling approaches use a combination of graphics and
text to describe the system in question. Exactly how that happens, and
what each part means is where the model’s conventions apply. It is also
interesting to note that almost all models contain some form of directed
graph. Exhibit 9 shows some types of directed graphs.
The notational system: the shape, size, and color of the nodes and arcs;
the positioning and connection of the model elements; the syntactic rules
for the elements; and, most importantly, what the model elements repre-
sent are the modeling conventions. But there are a lot more considerations ...