ER model is a high-level conceptual data model. The goal is to create a simple description of the data that closely matches how users and developers think of the data.
The entity-relationship (ER) data model allows us to describe the data involved in a real-world enterprise in terms of objects and their relationships. It is widely used to develop an initial design of a database.
It provides a set of useful concepts that make it convenient for a developer to move from a basic set of information to a detailed and precise description of information that can be easily implemented in a database system. It describes data as a collection of entities, relationships and attributes.