Accountants can use data flow diagrams (DFDs) to depict the physical flows of data through an AIS (like document flowcharts), or the logical flow of data through an AIS (like system flowcharts). Like document or system flowcharts, their main objective is to document data flows in an orderly, graphic, and easily-understood format. But DFDs use fewer symbols than either document or system flowcharts, and do not require columns (like document flowcharts). Discuss how a document flowchart assists each of the following individuals: A systems analyst. A systems designer. A computer programmer. An auditor. A data security expert. Flowcharting is both an art and a science. Guidelines can be used to make better flowcharts. What are these guidelines for document, system, and data flow diagram flowcharts? What are the four symbols used in data flow diagrams? What does each mean? Discuss why data flow diagrams are developed in a hierarchy? What are the names of some levels in the hierarchy