Protege is used as a tool to manage and manipulate the knowledge base ontology.
On the left is the hierarchy of concepts.
On the right are properties of the particular concept.
In the picture, the concept HeatFluxBurner, which is in the hierarchy DataTypeDevice -> CombustionInstrument -> FlameBurner. In this case, the properties on the right are the properties of the HeatFluxBurner, for example, the attributes and the subsystems.