# Conceptual model

The following diagram shows a simplified version of the entities you can interact with via the API. Refer to the endpoints documentation for a complete and up to date description of the entities.

## Hierarchical structure
Organizations are the top-level entities that own users, users own replicas, and replicas are trained on training data (knowledge base).

## Access control
Organizations cannot access each other's data (e.g. users, replicas, training data, ...).

A user can interact with a replica if they own it, or if the replica is public.

Chat history is owned by both users and replicas.

## Diagram
![Conceptual Model Diagram](https://sensay-io.github.io/api/conceptual_model_diagram.svg "Conceptual Model Diagram")