Bounded Contexts act as boundaries of Domain Concepts

A Bounded Context is a theoretical (or actual, if using Microservices) boundary within which concepts related to a model hold true without exceptions. Within the context, the Ubiquitous Language used to define a concept is always valid and right.

Within a Bounded Context, there are no contradictions in the model or concepts. If there is confusion, either the concept has to be renamed (which rarely happens), or a new Bounded Context has to be created. This is largely due to differences that emerge in the Ubiquitous Language.

For example, Account in the User Bounded Context may relate to a real person and attributes/behaviors associated with authentication and profile management. The same Account in the Book-keeping Bounded Context may relate to a bank account which has a Cr/Dr Balance.

But boundaries may have to be drawn to depict different technical concepts too, like an in-memory database model vs. a relational database model.

Common concepts shared between Bounded Contexts are linked together.