Java Persistence API (JPA) provides POJO (Plain Old Java Object) standard and object relational mapping (OR mapping) for data persistence among applications. Persistence, which deals with storing and retrieving of application data, can now be programmed with Java Persistence API starting from EJB 3.0 as a result of JSR 220. This API has borrowed many of the concepts and standards from leading persistence frameworks like Toplink (from Oracle) and Hibernate (from Apache). One of the great benefits of JPA is that it is an independent API and can nicely integrate with J2EE as well as J2SE applications.
Shunmuha Raja explains
Introduction to Java Persistence API(JPA)
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