Business Rules

A Domain has many process representing the workflows of people and data through itself. These processes are aligned to certain guidelines or norms whose purpose is to ensure that the changes in the system (both real-life as well as software systems) are allowed only when a set of expectations are met. These expectations are codified in the form of the Domain's Business Rules.

In DDD, a domain can be associated with two kinds of Business Rules: Business Invariants and Corrective Policies. Business Invariants are never to be broken, while Corrective Policies can be broken but need to be rectified later as a background process.