Java Persistence API (JPA) annotations are used to map Java objects to database tables and columns. JPA provides a set of standard annotations that can be used to define the mapping between the Java objects and the database tables.

Some of the commonly used JPA annotations include:

• @Entity: This annotation is used to specify that a Java class is an entity class, which represents a table in the database.

• @Table: This annotation is used to specify the name of the table in the database that the entity class maps to.

• @Id: This annotation is used to specify the primary key field of the entity.

• @GeneratedValue: This annotation is used to specify how the primary key should be generated, such as using a sequence or an auto-increment field.

• @Column: This annotation is used to specify the name and properties of a column in the database that a field in the entity maps to.

• @OneToMany: This annotation is used to specify a one-to-many relationship between entities.

• @ManyToOne: This annotation is used to specify a many-to-one relationship between entities.

• @ManyToMany: This annotation is used to specify a many-to-many relationship between entities.

• @JoinColumn: This annotation is used to specify the name of the foreign key column in a relationship between entities.

These are just a few of the JPA annotations that are available. JPA provides a rich set of annotations that can be used to define the mapping between Java objects and the database tables. By using JPA annotations, you can write Java code that is simpler, more expressive, and easier to maintain.