As we saw in the previous section, GenServer lets you create a server process that can handle synchronous and asynchronous interactions with its clients, while also giving you a way to handle other kinds of low-level messages (sent using Process.send/3) with the handle_info/2 callback.
However, there will be times when you don't want to control whether the communication is sync or asynchronous. You don't need to handle out-of-band messages, you just want to spawn a process that properly stores information in its internal state and shares it when needed. In this case, a GenServer feels overkill for the task at hand.
Instead, you can employ an Agent and get it over with. Think of it as a GenServer tailored to only perform internal state ...
