A DFD consists of the following main elements:
Process— A software module that transforms or manipulates data.
Data store— A location for storage of data. This can be a registry, file, log, usage history, or most recently used list.
Entity— This is a consumer or creator of data. This can be a person, Web site, company, or external process.
Dataflow— An arrow that depicts the flow of data to or from a data store, entity, or process.
This section provides tips and techniques to make the basic DFD more readable.
Using numbers on the various elements helps remove any ambiguities that may exist when there are multiple elements with the same or a similar name. These numbers ...