[mejthemage]

I didn't know you could specify a DNS server with a name. So does dig first look up that name using whatever DNS server is normally configured to determine where the intended DNS server is?

NextDNS gives you a name that you can put in certain UIs (like "Private DNS" in Android) -- I always assumed there was just something special about those.

[micheljansen]

Almost. Every domain (or rather “zone”) has an authoritative name server that maintains the dns records for that zone. When you perform a lookup from your device, it will ask your configured name server (from your ISP or 8.8.8.8 and friends), which will then look up the authoritative server and contact it to resolve the answer and send back the result (which it caches).

You can tell dig to bypass the normal way of things and ask a specific name server instead. This can be useful to bypass caches and debug DNS issues.