Could you explain what is meant by the term 'abstract model' in the context of system design?

An abstract model in system design is a simplified representation of a real system that highlights key entities and their relationships, hiding implementation details. Such a model helps focus on the main components and their interactions, facilitating understanding and further development of the system.

For example, in designing an online store, an abstract model may include entities like "User," "Order," "Product," and the relationships between them, without describing specific storage technologies or interfaces. This allows developers and business analysts to have a common understanding of the system's structure and requirements.