I am new to Oracle datatype, I need some immediate help..

Can anyone please guide me how to use LOV oracle datatype
and what it is.?

Whether NVARCHAR() is better than VARCHAR2()?
Does NVARCHAR() supports localization(different languages) and how is it?

For long text fields should i keep CLOB or TXT as datatype.

Thanks in advance.

Regards,
Komal.