Understanding roles
In real-life scenarios, we will mostly be configuring web servers, database servers, load balancers, middleware queues, and so on. If you take one step back and look at the big picture, you will realize that you are configuring groups of identical servers in a repeatable fashion.
To manage such infrastructures in the most efficient way, we need some abstraction which allows us to define what we need to configure in each of these groups, and call them by name. That's exactly what roles do. Ansible roles allow us to configure groups of nodes at the same time, without repeating ourselves. Roles also provide a way to create modular code, which then can then be shared and reused.
