| Interface | Description | 
|---|---|
| Application | An application is the root of the entity hierarchy. | 
| Effector<T> | An operation of some kind, carried out by an  Entity. | 
| Entity | The basic interface for a Brooklyn entity. | 
| EntityType | Gives type information for an  Entity. | 
| Feed | A sensor feed. | 
| Group | An  Entitythat groups together other entities. | 
| ParameterType<T> | Similar to the concepts in the JMX  MBeanParameterInfoclass. |