The Authentication view allows you to control account access to the database. This includes system users (root, namespace, and database) as well as scope access.
The first three panels are used to configure root, namespace, and database access to the database, also known as system users. These panels list out users, which you can modify using the pencil button.
Additionally you can press the + buttons to add new users to the database.
The last panel lists out configured authentication scopes which, much like the other panels, allows for the creating and updating of scopes. Visit the documentation on scope authentication to learn more about what to enter into the sign up and sign in query fields.