Characteristics: Every domain name is divided into a hierarchy. The top-level hierarchy appears after the last dot in a domain name. In the example above, .com is the top-level domain name. Sharkeylaw is the second-level domain, and www is the subdomain. Domain name disputes concern the second-level name. This is because it is impossible for two identical second-level domain names to exist under the same top-level domain.
Registration: United Technologies and United Healthcare would probably both like to have the domain “united.com.” It is, however, United Airlines that uses the domain. Why would United Airlines trump United Technologies, United Healthcare, or any other business operating under the name “United?” Presuming that united.com has not been bought, sold, or transferred since its initial registration, it is because United Airlines was the first to apply to register the domain. In order to register a second-level domain name under a top-level domain, a request must be made to the registrars that have the power to assign names for that top-level domain. Registrars of .com, .net, and .org domain names are accredited by The Internet Corporation for Assigned Names and Numbers (ICANN), a non-profit formed to control domain name and perform similar functions. All registrars assign domain names on a first-come, first-served basis, regardless of the registrant’s trademark rights in the name.