A user of the screen reader. Corresponds to a hardware device that users use. This class is a facade that acts as a one stop shop for all screen reading services on a per user basis. Multiple screen reader users can exist simultaneoulsy to facilitate local multiplayer and users can opt in or out of receiving screen reader feedback by registering and unregistering with the screen reader respectively. A screen user is inactive by default when it is first registered through the screen reader. Users must explicitly activate the screen reader user after successful registration with the screen reader to use its services. Responsibilities of the class are: