Classification (CLA)
Classification (CLA) is a Relation between a specific PLOGESTRB entity and the class (Concept) to which it belongs.
Example: O this apple - CLA - C apple
; O another apple - CLA - C apple
.
Classification is vital for querying the database: it allows to find specific instances of a generic Concept (e.g., all apples) but also, through the Superclass tree of Concepts, more general classes (e.g., any instances of fruit).