A data model is a collection of concepts that can be used to
describe the structure of a database and provides the necessary
means to achieve this abstraction whereas structure of a database
means the data types,relationships and constraints that should hold
on the data.
Data model are divided into three different groups
they are
1)object based logical model
2)record based logical models
3)physical models
Types:
Entity-Relationship (E-R) Data Model
Object-Oriented Data Model
Physical Data Model
functional data model