The data that relate terminology and concept definition support the classical thesaurus functions (Soergel 1996, Doerr and Fundulaki 1998):

• guidance for the user to find a concept in the thesaurus,

• clarification of its meaning,

• unique identifiers to be used for effective identification, indexing and classification of the (archaeological) material

• preservation and update of information, through a process of proposals/submission of new terms or of modifications on introduced terms. This process has been structured in another schema (fig 1). It is regarded as a necessary process since it contributes to the completeness and final edition (through a version control) of the period thesaurus (Doerr and Fundulaki 1998).

• a frame of an ontology for standardization of elements. (Doerr and Fundulaki 1998). An ontological analysis, which aims at supporting reasoning about the relations between periods, and periods and finds.