There's really nothing you can't do with them. Since I'm now venturing into the scary world of databases, I want to make sure you know what I mean by ftang when I say ftang. A database is a collection of tables. A table is a collection of records. A record is a collection of fields.
Fields are the basic units of information in a database.
So, a database is a big bad backend system containing all of your information. Remember, information is power. In this article, we want to map between database records and Java objects. That means we want to be able to automatically translate between a Java User object and a particular record within, for example, an employees table in a database. Consequently, the name variable of the Java object will be mapped to the name field of the database record, and vice versa.