There are only three roles in Scrum: Product Owner, Scrum Master and Development Team. It's not
allowed to define new roles and the Development Team members should not have any titles; they are
all "developers". It is so, because we want all of them to be accountable for everything and to
collaborate with each other.Each person has his/her own area of expertise, such as testing, and that
person will be more focused on testing tasks but it doesn't mean that we can call the person
"tester".