.aero
The TLD designated for the air transport industry, available only to aviation community members.

.biz
The .biz TLD is a designated suffix for businesses. Domains using the .biz extension must be used for business or commercial use.

.com
Short for .commercial. Domain names with the .com extension are the most popular and can be purchased by any individual or business in any country.

.coop
This TLD is available to cooperatives, cooperative service organizations and wholly owned subsidiaries of cooperatives.

.edu
Generic, restricted top-level domain. Available exclusively to degree-granting educational institutions of higher education that are accredited by one of the six U.S. regional accrediting agencies.

.info
The .info domain extension is available to the general public.

.mil
Generic top-level domain operated exclusively by the United States Military.

.museum
This TLD is available only to museums, museum organizations and individual members of the museum profession.

.name
Available to the general public, .name email addresses are listed as firstname@lastname.name or lastname@firstname.name. Web sites are listed as www.firstname.lastname.name.

.net
Short for .network. This domain extension was originally designed to be used by technical web sites. However, this extension can be registered by anyone.

.org
Short for .organization. Originally for non-profit organizations that did not fit under the .com or .net extension. However any individual or business may now register a .org domain name.

.pro
The .pro suffix was created for certified professionals including lawyers, doctors and accountants.

.us
Country-code top-level domain. Available exclusively for residents of the United States and its territories.

.ws
Generic top-level domain name. Stands for "Web site."