# Data models
This API allows manage data model. You can learn more about data models in the IoT Concepts section.
DMM datamodels are already provisioned by default in the platform. It exists special conditions for them:
- It is not possible remove them.
- Categories can not be add or remove.
- Datastream of category can not be add or remove.
- It is not possible change the following fields:
If the conditions are violated the platform will throw an error.
By default the platform automatically generates several DMM data streams through which it can be retrieved the history of different monitoring & management parameters. See also Datamodels to know the list of data streams.