An Entity Relationship (ER) Diagram is a sort of flowchart that shows how "entities" in a system, such as people, things, or concepts, interact with one another. ER Diagrams are most commonly used in the disciplines of software engineering, corporate information systems, education, and research to build or troubleshoot relational databases. They are sometimes referred to as ERDs or ER Models because they employ a predefined collection of symbols like as rectangles, diamonds, ovals, and connecting lines to illustrate the interconnectivity of entities, connections, and their properties. They reflect linguistic structure, with items acting as nouns and connections acting as verbs. ER diagrams aid in the analysis of databases used in business process re-engineering as well as the modeling of a new database architecture.