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Data Flow Diagrams Definition

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DFD or Data flow diagram definition is essentially a depiction of the system’s flow. DFD is typically utilized by persons who work in or pursue careers in the field of information systems. On the basis of these two definitions, we may conclude that DFD is a description of the information processing flow from input to output. The focus of data flow diagrams will shift from data storage to the flow of information, its source and destination.

Understanding Data Flow Diagrams

DFD is a map of the flow of information for each process or system, based on the Lucidchart page. DFD is a description of how data can be processed by a system from the output or input side, according to the SmartDraw page. Data flow diagrams can typically be used to explain or assess an information system. This diagram can also be utilized during the application development process.

The majority of analysts like data flow diagrams over other types of diagrams. Why? Because DFD can assist them in creating a diagram of a system, which may subsequently be given to the programmer. The programmer will next create code based on the analyst’s data flow diagram instructions. Many system processes are difficult to define verbally. Utilizing data flow diagrams that are visually generated might further simplify the process.

There are numerous symbols available for usage with DFD, including circles, rectangles, and arrows. Each symbol has a unique significance and will be labeled to describe each stage. You can manually create a rudimentary DFD. However, you may also use specific tools to accelerate the creation process.

Data Flow Diagram Functions

There are essentially three primary functions of a data flow diagram:

System Drawing

The primary purpose of the data flow diagram is to depict the system. You may depict the system as a more functioning network using DFD. There are numerous network components that can be interconnected through data flows. So that you can comprehend every system flow.

Model Making

In addition to being used to illustrate systems, data flow diagrams can be used to develop a new model. You can zoom in on specific system functions to view a more detailed portion of the DFD. As a result, you can use key components as a guide when creating the model.

System Design Submission

The third purpose of the data flow diagram is to communicate the system’s architecture to outsiders. Using a graphical method, DFD is able to illustrate the data flow more readily. For this purpose, you can display a data flow diagram to a team of programmers, clients, system builders, or anybody else you believe should be aware of the system’s design.

Principal Guidelines for Drawing Data Flow Diagrams

According to the Lucidchart page, there are at least four fundamental guidelines for creating data flow diagrams:

Total Inputs and Outputs

Every data flow diagram must contain at least one input and one output. The rationale is that the data flow diagram must be able to describe the system’s flow from start to finish.

Data Store Connection

Each data storage must be connected to at least one input and one output, per the following rule of DFD. Consequently, the data store will eventually be able to hold all system-entry data.

The Data Archive Must Be Processed

Any data saved in the data storage must be capable of undergoing a transformation to become an output.

Process Placement

Each process in the DFD must undergo multiple more processes or be saved in a data store.

Symbols Utilized Within Data Flow Diagrams

External Parties

A terminator or external entity is the first symbol you can use in a DFD. This icon represents an entity from outside the system. They might be organizations, persons, firms, divisions, or other types of systems. This external entity will either offer input to the system or receive output. This symbol for a data flow diagram can be represented by a box or rectangle.


The DFD describes a process carried out by a machine to transform input into output in a variety of formats. The symbol for this is a circle or rectangle with a line inside.

Data Store

A data store is a file that can temporarily store data or information. Thus, the data repository is a database. This data repository typically takes the form of a table, making it easy to process. Each data repository is required to have at least one input and one output. The symbol for this data repository is two parallel lines.

Data Stream

Data flow refers to the flow of data between a terminator, a process, and a data storage. This is symbolized by a directional arrow.


This is the data flow definition, so a data flow diagram or DFD is a visual depiction of the flow of processed data from input to output. You should also pay attention to data from financial statements. Why? As a result of the significance of financial statement data in formulating corporate strategies.