> Emacs' usage of ‘client’ and ‘server’ here refer to [...] simple control commands

Despite that, it still enables this:

> where runtime state is synchronized between the client and server over a network

On graphical X11 frames:

https://news.ycombinator.com/item?id=48864196

but it also enables having multiple TUI `emacsclient -c -nw` frames over SSH.