A top-level domain (TLD) is the last segment of a web address's domain name, and the highest level in the hierarchical Domain Name System. As such, it is also the last component of a fully-qualified domain name (FQDN).[1] It is represented by a sting of letters after the last dot in a web address. The most commonly used TLD is currently "com", which stands for "commercial".[2] Although many "com" addresses are not used for commercial purposes, most TLDs are used to designate the type or purpose of a website, as well as allow for more prime namespace on the World Wide Web. For example, Conservapedia's address is "www.conservapedia.com". In this case, the top-level domain is "com".
Example TLDs
There are currently over 1,500 registered top-level domains on the Internet, and this number is continuing to grow. These include the following popular ones:
.com - Commercial
.org - Noncommercial
.edu - US accredited postsecondary institutions
.gov - United States Government
.uk - United Kingdom
.net - Network services
.ca - Canada
.de - Germany
.jp - Japan
.fr - France
.au - Australia
.us - United States
.ru - Russian Federation
.ch - Switzerland
.it - Italy
.nl - Netherlands
.se - Sweden
.no - Norway
.es - Spain
.mil - United States Military
There are also many less popular ones, such as:
.gw - Guinea-Bissau
.ax - Aland Islands
.wf - Wallis and Futuna Islands
.yt - Mayotte
.sj - Svalbard and Jan Mayen Islands
.mobi - Consumers and providers of mobile products and services
.eh - Western Sahara
.mh - Marshall Islands
.bv - Bouvet Island
.ap - African Regional Industrial Property Organization
.cat - Catalan linguistic and cultural community
.kp - Korea, Democratic People’s Republic
.iq - Iraq
.um - United States Minor Outlying Islands
.arpa - Technical infrastructure on the web
[2]
Some companies such as American Express (".AMERICANEXPRESS") and Travelers Insurance (".TRAVELERSINSURANCE") have also registered TLDs for their companies. This kind of TLD typically sees very little usage across the web, due to the specialization of the names. They are also typically restricted, so only the TLD owner (in this case, the represented company) can register web addresses under it.