Basic value types usually map a single database value, or column, to a single, non-aggregated Java type. Hibernate provides a number of built-in basic types, which follow the natural mappings recommended in the JDBC specifications. You can override these mappings and provide and use alternative mappings. These topics are discussed further on.

Composite types, or embedded types, as they are called by the Java Persistence API, have traditionally been called components in Hibernate. All of these terms mean the same thing.

Components represent aggregations of values into a single Java type. An example is an Address class, which aggregates street, city, state, and postal code. A composite type behaves in a similar way to an entity. They are each classes written specifically for an application. They may both include references to other application-specific classes, as well as to collections and simple JDK types. The only distinguishing factors are that a component does not have its own lifecycle or define an identifier.

A collection type refers to the data type itself, not its contents.

A Collection denotes a one-to-one or one-to-many relationship between tables of a database.

Refer to the chapter on Collections for more information on collections.