The Value Of Flow Diagram Drawings
Flow diagram drawings are an essential component of information systems. A flow diagram drawing is constructed to graphically illustrate the flow of data in information systems. Flow diagrams drawings are also needed for other purposes such as visualization of structural designs where a context-level data flow diagram drawing is created initially, to demonstrate the interaction, linking the system and the external factors. When designers work on a new project, they first build a flow diagram drawing to briefly summarize the all the phases or cycles of a systems development. Drawing a flow diagram makes it easier for the designers to represent the whole project with clarity to the project sponsors and the end consumers. With the aid of the data flow diagram drawing, the users should be to picture the functionality of the system's operation, how the system will be completed and how it will be put into practice. A designer can compare his old flow diagram drawings with newly constructed flow diagram drawings to find out the contrast between them and thereby, can create more efficient systems. Flow diagram drawings can present the end user with the actual idea on how the physical data input affects the configuration of the structure of the entire system. A typical flow diagram drawing comprises of the following entities: 1. Terminators 2. Processes 3. Data Stores 4. Data Flow Terminators - Terminators are also known as the external entities and they are modeled as being in the exterior of the system in flow diagram drawing. Terminators illustrate the source of the information and final destination. In other words, the terminators illustrate how the data enters and exits the data flow drawing. Processes - These entities alter the process input and output while drawing a flow diagram. Data Store - The Data stores symbolize a process stage where the data rests. The data stores do not provide information on the duration of the data stores; therefore it can be considered that they gather data over an arbitrary period of time before it is finally processed. A data store also denotes fixed information that must be stored for the system to work properly. Data Flow - The data flows represent how the information flows between the terminators, process stages and the data stores. A designer constructs a flow diagram drawing by starting with a context level drawing. The initial drawing of the flow diagram shows the relationships between the system and the external system environment. The system is then further simplified to a lower level Data flow diagram drawing that includes a group of processes, data flows as well as data stores. Each of the processes is then further resolved into even lower sub-diagrams that contains associated processes. The process of decomposition is carried out until the required and adequate level of detail is achieved and the final outcome is called the primitive process. Flow diagram drawings are extremely important in engineering, information systems and particularly the manufacturing industry, where they are constructed so that designers can get an understanding of the entire process by taking a quick glance at the drawings. They are analogues to the architectural sketches, which provide us with the architect's impression of the designed infrastructure. |
