Domain Name System
Worldwide decentralized and distributed directory enabling the association of host/domain names (easily remembered by humains) to IP adresses (used by computers to exchange information between themselves).

Identification of a given individual/entity, managing many domain names. Each Registrar has its own scheme for handles.

The Internet Corporation for Assigned Names and Numbers (http://www.icann.org/) A technical coordination body for the Internet, regulating use of TLDs

Internationalized Domain Name
Also known as multilingual domain names. It gives the possibility to use more characters in domains names, besides letters and numbers, and specifically characters available in other alphabets, like accents.
A standard is being developed by the IETF.

Internet Engineering Task Force (http://www.ietf.org/) The IETF is a large open international community of people concerned with the evolution of the Internet architecture and the smooth operation of the Internet. They define standards.

( http://www.internic.com/ )
Registered service mark of the U.S. Department of Commerce, licensed to ICANN.

Name Server

A computer specifically configured to be able to resolve DNS queries, and eventually being authoritative for a given number of domain names.

Network Solutions Incorporated ( http://www.nsi.com/ )

Historically, company having received from the US gouvernment management of .com/.net/.org/.edu domain names After the end of the monopoly, company managing the Registry of those TLDs, while still being one of the Registrars for those TLDs. Have been sold to Verisign.

Entity that manages the centralized database of domain names registered in a given TLD (or more than one TLD). It is the authoritative source of information, which updates whois and root nameservers for the TLDs being handled with the content of its database. This structure has as clients Registrars, which operate on domain names for their clients. Each TLD has its own policies and working.

Entity accredited by ICANN in some TLDs being client of corresponding Registries to be able to register domain names.

Top Level Domain

Part of the domain name being on right, after last point. Example: .NET as in GANDI.NET Also called extension.

The list of existing TLD is managed by ICANN. They are subdivised in ccTLDs and gTLDs :

• ccTLD (country code TLD) : each country has its own TLD (which is the ISO code of the country). Examples: .fr for France, .uk for United Kingdom, .de for Germany, etc... New ccTLDs happen when new countries appear, like .eu
• gTLD (generic TLD) : TLD not bound to a given country. Historically they were only : .com .net .org .mil .gov .edu .int (and .arpa) Now there is also : .biz .info .name .aero .coop .museum .pro New gTLDs are created by ICANN.

All TLDs are technically working in the same way, and can be used the same way.

(http://www.verisign.com/)
Company handling digital certificates, having bought NSI, thus managing through its branch Verisign Global Registry Services some TLDs, while being Registrar through Verisign Registrar.

Directory to find the owner of a given domain name, or the contact person in case of problems.
This directory is searchable through multiple web sites, or through dedicated software.