An entity is a grouping of things with rules or data in common. Anentity often represents a group of people (e.g. children, applicants,
stakeholders) but it can also represent a group of objects (e.g. textbooks),
activities (e.g. assignments) or concepts (e.g. school terms).
By defining entities, the same set of rules can be used formultiple instances of the same type, and rules can be written which relate to
all of those instances.
A member of the entity group is called an entity instance. Forexample, if a family had 2 children, Sarah and Peter, Sarah would be one
instance of "the child" entity and Peter would be another instance of
"the child" entity. By creating an entity to represent "the
child", information such as the child's age can be collected for each