Poettering: systemd for Administrators, Part IX

I realise this is offtopic but since you use avahi I wonder if you could give me some idea of what it's actually for. It's one of those random daemons that get installed automatically on new Linux installs but doesn't seem to do anything, and reading the wikipedia page leaves me none the wiser.

I gather it's only of relevance if you have a network which doesn't have a router doing DHCP and DNS, but you still want local name resolution; it that correct? Certainly I've always removed it with no problems - discovery of other machines and file shares still works fine.

With PulseAudio I've worked out that it's useful if one or more of the following cases applies:
* You want to hotplug audio devices frequently and have the appropriate one chosen automatically
* You want per-application volume controls for applications that don't have their own volume setting
* You want to be able to transfer a running audio stream between devices.
None of these apply to me which is why it seemed useless to me for ages and I couldn't figure out why anyone might want it.

Is there a similar list of cases in which one might want to use avahi?