Hibernate is an Open Source persistence technology. It provides Object/Relational mapping library. It solves object-relational impedance mismatch problems. Hibernate works as a bridge between application and database

      Applications
           |
       Hibernate
           |
     Database Server

Hibernate provide a way of mapping of applications class to the database table. It maps each class properties to the corresponding columns of table. After mapping to the table, all operations are performed by using the object of class in which table is mapped. So the overhead of interacting with the database overcomes.

Hibernate Examples