Registry is the organization that maintains the top level domain database and hosts the TLD name server service. The Registry also sets the domain rules. For example, the Registry for the .FI TLD in Finland is the Traficom.
Registrar is the company/organization that has a contract with the registry and actually registers the domains.
Zone is the official registrar of .FI, .EU, .EE, .LV, .LT, .NL domains, having agreements with the respective TLD registries. For the remaining TLDs, Zone cooperates with other registrars.
Registrant is the natural person/organization (legal person) in whose name a domain name is registered or who applies for registration of a domain name.
Administrative contact is the registrant’s representative (natural person) who is entitled to perform all registration services on behalf of the registrant. The administrative contact must be authorized by the registrar to carry out all domain-related activities on their behalf. If the registrant is a legal person, the administrative contact is the person who orders the registration services from the registrar.
If the registrant is a private individual, he will normally also act as the administrative contact. The administrative contact does not have the right of sub delegation. The administrative contact is responsible for the accuracy and authenticity of the information and documents provided about him/herself and the registrant.
Technical contact is a natural or legal person who, on behalf of the registrant, adds, modifies or removes domain name server records. If the domain registrant uses the services of a web hosting company, it is recommended to assign the company´s representative as the technical contact. However, if the domain registrant manages their own nameservers, they may appoint themselves as the technical contact.