ERD stands for Entity Relationship Diagram. It is a visualization of relationships between people, places, concepts, etc. in a database. For example, you can create a ERD to show how students register for classes. There are three components to a ERD: entity, relationships, and attributes. An entity is basically a noun. It describes a physical object, concept, or an event. Entities are represented by a rectangle in an ERD. Relationships in an ERD indicates how the entities are related to each other. The relationships are represented by lines in between two entities. Attributes are properties that describe an entity. There are different types of attributes: simple (cannot be split such as a name) , composite (can be split such as first and last name), and derived (attribute calculated from another attribute) (databasestar.com). Attributes can also be single-valued and multi-valued. Attributes are represented by ovals in an ERD.
Ben Brumm. (2022, September 26). A guide to the entity relationship diagram (ERD). Database Star. Retrieved March 2, 2023, from https://www.databasestar.com/entity-relationship-diagram/
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