As a software architect, it is important to understand the key concepts and patterns used in Domain-Driven Design (DDD). One of the most important of these concepts is the Aggregate. An Aggregate is a cluster of related objects that are treated as a single unit for data changes. It defines a boundary around a set of objects and a root entity and provides a way to enforce transactional consistency and isolate the persistence of the objects from the rest of the application. One of the key benefits of using Aggregates is that they provide a way to enforce transactional consistency. Another benefit of using Aggregates is that they provide a way to isolate the persistence of the objects from the rest of the application. Aggregates should be kept small and focused. Examples of Aggregates in the real world include: An e-commerce system, A banking system, A healthcare system. The specific Aggregates that are used in a system will depend on the domain being modeled and the requirements of the system. However, the key idea behind Aggregates is to define a boundary around a set of related objects and to ensure that changes to these objects are atomic and consistent.
