http://wiki.oracle.com/page/scott%2Ftiger
Almost every Oracle database has had an account called SCOTT with password TIGER. It is named after Bruce Scott (one of the original Oracle employees) and the password is the name of his daughter's cat. This schema contains the EMP and DEPT tables used in innumerable demos. In recent versions of the database, this account is locked by default and must be unlocked with
SQL> ALTER USER SCOTT ACCOUNT UNLOCK;
Oracle XE inexplicably doesn't have this classic account, but you can add the user yourself and fill it using the demobld script.
Later versions has an additional demo schema called HR with password HR. This schema contains many additional database objects to allow demonstration of newer database features.
