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What is a Top-Level Domain?

Top-Level Domain

A domain name has a hierarchical structureBIn the URL above the top of the structure is .com on the far right. This is known as a top-level domain (TLD). To the left of the TLD is the second-level domain (SLD) (gmoregistry in the example above).
The allocation domains and IP addresses is globally coordinated by ICANN.to ensure repition is avoided.

About Registries and Registrars

ICANN
ICANN (Internet Corporation for Assigned Names and Numbers) is a US based non-profit organization responsible for managing the assignment of domain names and IP addresses. ICANN also holds the authority to designate official domain registrar services.
Registry
A registry is an organization that maintains a database of domain name data for a particular domain. For example VeriSign, Inc is the registry for .com and .net, and .Public Interest Registry manages the .org domain. Registries are required to maintain neutrality and, guarantee equal access to the Shared Registry System (SRS) for all registrars.
Registrar
ICANN accredited registrars can directly register domain data into a registry database under contract with the relevant registry. While there is only one registry for each top-level domain, multiple registrars exist to promote competitive pricing and services.

Top Level Domains

There are two main types of top level domain.

gTLD
Generic top-level domains (gTLD) are general usage domains. Before ICANN was formed, there were eight gTLDs, seven more gTLDs were introduced after ICANN was established in 2000, and a further six were added in 2003. Currently, there are 21 gTLDs including .com, .net, .org, .info, or .biz.
ccTLD
Country code top-level domains (ccTLD) are two-letter identifiers that correspond to ISO 3166-1 country codes. There are roughly 250 different ccTLDs in existence,, including .jp for Japan, .us for United States, .cn for China and.uk for United Kingdom.

How GMO Registry can help you.

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