Where do domain names come from?
Each Top Level Domain (TLD) or domain extension is managed by a Registry Operator (RO). Each Registry Operator is responsible for maintaining the registry database for all domain names, associated registration data and registrant contact information for their respective domain extension. Registry Operators are also responsible for publishing the zone file which includes data on the location of each domain name.
A Registry Operators may operate a single TLD or multiple TLDs. Some Registry Operators also sell their technical services to other Registry Operators which choose to concentrate on the sales and marketing of their domain extensions while outsourcing the more technical aspects.