| No | Word | Definition |
| 1 | The E-R Model | The Entity-Relation model, one of the most widely used approaches for database conceptual modelling. |
| 2 | E-R Entity | The basic object in an E-R model. It represents an object in the real world that can be distinctly identified. |
| 3 | E-R Weak Entity | An entity that its existence is dependent on another entity. |
| 4 | E-R Attribute | Represents a property of the entity that it belongs to. |