What is the difference between managers, controllers, services, handlers, helpers?

I see a lot of these terms in the naming conventions: managers, controllers, services, handlers, helpers and I’m wondering when I should use each of these terms? Do some of these terms usually appear mainly on the server or client side?

Mainly its used for the Server/Client for example, Say its a FPS game such as arsenal.

Instead of having multiple scripts/localscripts in the StarterPlayer or StarterGui they just have 1 big script named “Client” or “ClientHandler” and such.

With the server, Instead of having multiple scripts in the ServerScriptService you could just have 1 which handle’s the whole framework of the game. I don’t know if I understood your question properly but I hope this answers it.