The OWB Repository

A major feature of the architecture in OWB is the single, unified OWB Repository for the database instance, which is pre-seeded with a schema and database objects. The runtime environment and the design environment reside in this single repository. The repository schema, named OWBSYS, gets created when you install Oracle Database. Once the database is installed, you do not need to perform additional actions, other than unlocking the OWBSYS and OWBSYS_AUDIT accounts.

Note:

OWB release 11g stores all repository objects in the OWBSYS schema, which is created as part of every Oracle release 11g database. The OWBSYS database user is also registered as an OWB user. Administrators and developers generally will register other database users and assign them required privileges, rather than using the OWBSYS account directly.
You can create multiple repositories if you prefer to separate the runtime and design environments; however, this is not recommended.