Category is a single division of collectives of Nouns to be grouped under. Example Security, Personal Care, Furniture or Stationery

A Noun is used to identify a Class of items assigned to a select category, any member of a class of words that typically can be combined with Modifier to serve as the subject of a verb, can be interpreted as singular or plural, a word that is the name of something (such as a Item or Service) Example Camera, Balm, Chair or Pen.

A Modifier is a Sub Class (adjective) that enriches the Noun to identify the item for what is and not what it is used for. It allows collection of a set of Attributes that specifically describes features of the item. Example Camera : Digital, Balm: Lips, Chair : Student or Pen : Roller Ball

A Sub class or division of items or things regarded as having the same set of Attributes. Or not classifiable due to the unavailability of information. General practice is to park the item in a Generic state until additional information can be provided.

Attributes are used to describe specifications or features which distinguish one article from another and are specific to a Noun / Modifier pair. Example Pen : Roller Ball, Type, Color, Size , Features, Material, etc.