What is the primary role of "Entities" in OutSystems?

In OutSystems, the primary role of "Entities" is to define the database structure and represent the data model of the application. Entities are used to create and manage the data that the application will manipulate, representing the core concepts and relationships within the application's domain. This involves defining attributes (fields) and their data types, as well as establishing relationships between different entities.

By structuring the data model correctly through entities, developers can ensure that the application interacts with the database efficiently, facilitating operations such as creating, reading, updating, and deleting data. This is crucial for building robust applications that require a well-defined data architecture to function properly.

The other options relate to different aspects of application development. For instance, while the user interface layout is crucial, it is managed through other components in OutSystems, not entities. Similarly, the security model is defined through roles and permissions rather than entities, and business logic is typically handled through actions and logic flows rather than directly through the data model.