Oracle default number of login username and password

The default user has so few, SYSTEM,SYS,SCOTT,HR, General Scott and HR as your practice users.
The default password for system is the manager
The default password for SYS is change_on_install
To practice the user, Oracle 10g needs to be unlocked later.
After logging in with SYS or the system user, use the following command to unlock
Alter user Scott identified by Tiger account unlock;
Alter user HR identified by HR account unlock;
Where Scott/tiger, hr/hr is the user name password.

Oracle default number of login username and password