.COM: Short for .commercial. Domain names with the .com extension are by far the most popular, and can be purchased by any individual or business.
.NET: Short for .network, this domain extension was originally designed to be used by technical Web sites. However, domains using this extension can be registered by anyone.
.ORG: Short for .organization. Originally designated for non-profit firms and any other organizations that did not fit under the .com or .net extension, any individual or business may now register a .org domain name.
.AERO: The TLD designated for the air transport industry. Available only to aviation community members, this domain suffix is now live and fully functional. You can find more information on this TLD here: http://www.nic.aero/.
.BIZ: The .biz TLD is a designated suffix for businesses. Domains using the .biz extension must be used for business or commercial use. This suffix is fully active. http://www.neulevel.biz/ has more information on the .biz suffix.
.COOP: This TLD is available to cooperatives, cooperative service organizations and wholly owned subsidiaries of cooperatives. You can find more information on the .coop suffix here: http://www.nic.coop/.
.INFO: The first unrestricted top-level domain since .com, .info domains are available to the general public. You can find more information here: http://www.nic.info/gateway.
.MUSEUM: This TLD is available only to museums, museum organizations and individual members of the museum profession. More information on the .museum TLD is available at http://musedoma.museum/.
.NAME: Available to the general public, .name email addresses are listed as email@example.com or firstname.lastname@example.org, while Web sites are listed as www.firstname.lastname.name. More information on the .name TLD is available here: http://www.nic.name/.
.PRO: The .pro suffix was created for certified professionals including lawyers, doctors and accountants. RegistryPro, the organization in charge of administering .pro domains, has initiated steps to set up the new registry, and anticipates taking registrations in late 2002. More information is available at http://www.registrypro.com/.