Registries manage the sale of all domains for the domain endings (top-level domain or TLD) they own. You can think of a registry as the wholesale and the registrar (Google Domains) as the retail. Customers, individuals, businesses, and organizations buy domain names from the registrar, and the registrar registers the domain names it sells with the registry.
Each registry manages the administrative data for the domains and subdomains under its authority, including the zone files that contain the addresses of the name servers for each domain. Each registry maintains a database that contains registrant information for the second-level domains (google.com, example.com) beneath the top-level domains (.com) the registry manages.
A registry operator is an organization that maintains the administrative data for one or more top-level or lower-level domains. For example, VeriSign is responsible for several top-level domains, including the .com, .net, and .name domains. A registry operator is given authority for a domain through ICANN.
Some registries have specific Terms of Service documents for the domains they sell. These spell out the rights, responsibilities, and requirements for registrants (customers), registrars, and the registry. When you purchase a domain name, you must agree to these terms of service. Review our list of domains endings for more information on their registries.