If you want to create a new user account, you can log in as SYSTEM and use the CREATE USER command as shown in the following example:

>.insqlplus /nolog

SQL> connect SYSTEM/globalguideline

Connected.

SQL> CREATE USER DEV IDENTIFIED BY developer ACCOUNT UNLOCK;

User created.

Note that CREATE is a SQL statement, so you need to terminate it with ";". This command creates a user called "DEV", with a password of "developer". You can test this account by log in with DEV from SQL*Plus.