.. avmetadata::
   :author: Noha
   :satisfies: ERD
   :topic: ERD

ERD Model definition & uses
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What is ERD?
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ERD is stands for an entity relationship diagram, is a high level data model in the form of graphical representation that describes relationships among people, objects, places, concepts or events within a database system. An ERD uses data modeling techniques that can help define business processes and serve as the foundation for a relational database. Simply it simulates the real world concepts.


Why ERD is useful?
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1- It develops a very simple and easy design view of data (conceptual design).

2- ER diagrams can be shared with colleagues and their simplicity makes them ideal even for non-technical stakeholders. 

3- As it provides a visual starting point for database design, it can also be used to help determine information system requirements throughout an organization.

4- The diagram also makes it easier to spot potential problems and correct them before moving on to the later stages of the design process.

5- After a relational database is completed, an ERD can still serve as a reference point, should any business process re-engineering be needed later.

**V.I. Note:** In spite of considering ERD as a conceptual design model, ERDs can generally depicted in one or more of all other model types (logical, physical).