Primitive data models:-In this approach objects are represented by record structures grouped in filestructures.The main operations available are read and write operations over records.


Classic data models:-These are the hierarchical, network and relational data models. The hierarchical data model is an extension of the primitive data model discussed above. The network is an extension of the hierarchical approach.


Semantic data models:-The main problem with classic data models such as the relational data model is that they maintain a fundamental record-orientation and semantic information must be applied by the user. Semantic models attempt to provide more meaning to the information held in the database.