This System level 0 data flow diagram provides a high-level overview of the entire system or process being analyzed or modeled. The system-level 0 data flow diagram is intended to be a high-level overview of the system, displaying it as a single high-level process with its relationships to external entities. It should be understandable to many people, including stakeholders, business analysts, data analysts, and developers. The cascading levels can be nested directly into the diagram using these Data Flow Diagram layers, giving a cleaner look with easy access to the deeper dive. If they become sufficiently detailed, developers and designers can use the DFD to write pseudocode, a combination of English and the coding language.