Update Table From Column In Table

=== QUESTION ===
How do I update a field in a table from another field in the same table?

=== RESPONSE ===
You can perform a SET for a field from another field in the same table.

- UPDATE [Northwind].[dbo].[Employees]SET [TitleOfCourtesy]=([Firstname])
- SELECT TITLE,TITLEOFCOURTESYFROM EMPLOYEES