ER model

An Entity–Relationship (ER) model is a visual way to organize and represent data in a database. It shows different categories of information ("entities") like customers or products and how they relate to each other ("relationships"). For example, a customer may place multiple orders, and each order is linked to a specific customer. The ER model uses diagrams with boxes for entities and lines for relationships, helping designers plan how data is structured and connected. This approach ensures data is stored efficiently and can be easily retrieved or updated when needed.