Source : Free On-Line Dictionary of Computing

knowledge representation
     
        The subfield of {artificial intelligence} concerned with
        designing and using systems for storing knowledge - {fact}s
        and {rule}s about some subject.
     
        A body of formally represented knowledge is based on a
        {conceptualisation} - an {abstract} view of the world that we
        wish to represent.  In order to manipulate this knowledge we
        must specify how the abstract conceptualisation is represented
        as a {concrete} data structure.  An {ontology} is an explicit
        specification of a conceptualisation.
     
        (1994-10-19)