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This area hosts reference material and other helps for various types of ICANN participants, such as country code managers, registrars, and registries. But even a non-technical Internet user can find items of interest, such as the Registrant Rights Agreement on the Registrars page. Feel free to explore!

Some of the resources this page links to include the following:

ccTLDs. References useful to country code managers and operators, including: letters of agreement between each ccTLD and ICANN; documents related to ccTLDs from entities such as ICANN Board, Staff, IANA, and the GAC; the full text of ICP-1; and more. Country code managers can find additional resources on the ccNSO website.

Compliance. Every ICANN-accredited registrar and registry has a contract with ICANN. Here’s where you can learn about all facets of ICANN’s Contractual Compliance Program, which helps both ICANN and the contracted parties each fulfill their end of the agreement.

Registrars. Information found here related to Registrars ranges widely, including a list of all accredited registrars, how to become a registrar, the registrar data escrow program, how dispute resolution works, and updates on domain-related policies.

Registries. Registry personnel can find a variety of helps here, such as: agreements, consensus policies, key ICANN contacts for registries, a list of valid top-level domains, a list of all accredited registries, and much more.

Internationalized Domain Names. You’ll find the lengthy, detailed history of IDNs here, along with technical implementation guidelines, publications and presentations about IDNs, an IDN glossary, ICANN blog entries about IDN updates, and more.

Policy. Links here present background, updates, and announcements about important areas of Internet policy currently being addressed by the ICANN community’s bottom-up, consensus based, policy development process.

Domain Name System
Internationalized Domain Name ,IDN,"IDNs are domain names that include characters used in the local representation of languages that are not written with the twenty-six letters of the basic Latin alphabet ""a-z"". An IDN can contain Latin letters with diacritical marks, as required by many European languages, or may consist of characters from non-Latin scripts such as Arabic or Chinese. Many languages also use other types of digits than the European ""0-9"". The basic Latin alphabet together with the European-Arabic digits are, for the purpose of domain names, termed ""ASCII characters"" (ASCII = American Standard Code for Information Interchange). These are also included in the broader range of ""Unicode characters"" that provides the basis for IDNs. The ""hostname rule"" requires that all domain names of the type under consideration here are stored in the DNS using only the ASCII characters listed above, with the one further addition of the hyphen ""-"". The Unicode form of an IDN therefore requires special encoding before it is entered into the DNS. The following terminology is used when distinguishing between these forms: A domain name consists of a series of ""labels"" (separated by ""dots""). The ASCII form of an IDN label is termed an ""A-label"". All operations defined in the DNS protocol use A-labels exclusively. The Unicode form, which a user expects to be displayed, is termed a ""U-label"". The difference may be illustrated with the Hindi word for ""test"" — परीका — appearing here as a U-label would (in the Devanagari script). A special form of ""ASCII compatible encoding"" (abbreviated ACE) is applied to this to produce the corresponding A-label: xn--11b5bs1di. A domain name that only includes ASCII letters, digits, and hyphens is termed an ""LDH label"". Although the definitions of A-labels and LDH-labels overlap, a name consisting exclusively of LDH labels, such as"""" is not an IDN."