I'm familiar with flow-charting and ERD (Entity Relationship Diagrams), but what is a Data Flow diagram? I guess the point I'm getting at is this: In other industries, diagrams like blueprints or CAD models are required because they have to move from the virtual to the physical. In software, the "model" could very well be the software, if there was an environment that saw it that way, no?

>>To do full -cycle projects, flow charting skills are absolutely necessary for an outsider (like me) to specify, plan and schedule a big system. There is no substitute.
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>Flow charts, AND Data Flow Diagrams .... :-)