User personas describe different types of users of the product. Each persona provides a realistic description of a typical user or group of users who behave similarly or have similar expectations of the system.
The idea behind the Persona is that for software to work effectively, it must be developed for specific people. Unlike actors, personas are not the roles that people play.
Extraordinary types of users that might interact with the system are called extreme personas.
A Persona used in the user-story template could look:
As <persona> ,
I want <what?>
so that <why?>.
