DNS hosting to control where you host on the Internet
The DNS (domain name system) is what makes web addresses like www.dedicateddns.eu actually work. It relates the domain name to an IP address such as 193.111.200.100, the 'real' underlying address of the server.
So, as well as email hosting and web hosting, every website or email address also needs DNS hosting.
You don't tend to hear so much about this, because it's usually thrown in with one or more of the other services.
But once your setup moves beyond a simple website and hosted email setup, DNS hosting is something you need to think about.
DNS hosting
A DNS hosting service is a service that runs Domain Name System servers. Most, but not all, domain name registrars include DNS hosting service with registration.
Almost all DNS hosting services are "shared;" except for the most popular Internet sites, there is no need to dedicate a server to hosting DNS for a single website.
Many third-party DNS hosting services provide Dynamic DNS.
Most Internet users rely on their Internet Service Provider to manage their primary and secondary DNS on their behalf. It's definitely the simplest and easiest approach.
DNS hosting service is better when the provider has multiple servers in various geographic locations that minimise latency for clients around the world.
DNS can also be self-hosted by running DNS software on generic Internet hosting services.