A data flow diagram is a partitioning tool used for structured system analysis and design. It is used for making logical models of systems prior to updating them, and for mapping the changes you are going to make.
This sort of diagram follows the data throughout it's lifetime, noting where it is changed, stored and retrieved, but from the data's perspective.
It is a vastly misunderstood diagram, which contrary to what some people believe says absolutely nothing about how the processing is serialised, or if it is realtime at one extreme or batch processing at the other.
See also Data Flow Diagramming for a detailed explanation of the methods of dfd's.
last modified 03:06 2001/11/22