Data Model : A Data Model is collection of conceptual tools for describing data, data relationships, data semantics, and consistency constraints. A data model provides a way to describe the design of database at the physical, logical and view level.
Relational Model :
The relational model uses a collection of tables to represent both data and the relationship among those data. Each table has multiple columns and each column has a unique name, and these tables are known as relations.
We can also understand relational model as a record-based model, and the column of the table correspond to the attributed of the record type.
Entity-Relationship Model :
The E-R data model uses a collection of basic objects, entities and relationships among those objects.
Object Oriented Data Model :
Object-oriented data model can be seen as extending the E-R model with notions of encapsulations, methods (functions), and object identity. The Object-relational data model combines features of the object oriented data model and relational data model.
Semi-Structured Data Model :
The Extensible Markup Language (XML) is widely used to represented semi-structured data.