A dns zone:
- is composed of all labels of a domain name except the last one on the left.
- in foo.bar.com, the zone is bar.com
- in your.foo.bar.com, the zone is foo.bar.com
A zone defines:
- the administrator:
- the organization
If your nameservers are the nameservers of:
- Cloudflare, your apex zone is on the Cloudflare website/server
- Ovh, your apex zone is on the OVH website/server
Zones file are configuration files of the DNS nameservers that defines a zone.
They describe the namespace of that zone (the mail servers, …)