JDBC Interfaces Summary

Interface	Description
Driver	Connection factory
Connection	Database session; Statement factory This is a database session; a session is a sequence of transactions - but they're not concurrent or nested. While the connection is active, there can be one and only active transaction with periodic commits or rollbacks, but no nested transactions and no distributed transactions in jdbc 1.
DatabaseMetaData	Database info for a Connection (tables, indices, capabilities, field types, etc...)
Statement	SQL container; ResultSet factory
PreparedStatement	Precompiled SQL; possibly parameterized
CallableStatement	Stored procedure
ResultSet	Cursor for results of query You can think of a result set as a SQL cursor, it's not a container which holds results by itself. A result set has no persistence by itself, it's not serializable and you can't just save it to disk. jdbc 2 provides a new object called a rowset for this purpose.
ResultSetMetaData	Column information for a ResultSet