Internet users are no doubt familiar with ".com," but it is only one of 264 in the Internets master directories. In fact, according to the company that runs the directories, VeriSign Inc., ".com" accounts for only about half of all domain names.
Other popular ones include ".net" and ".org," and countries have their own suffixes as well, including ".de" for Germany and ".fr" for France. Theres even a legacy ".su" for the Soviet Union in the databases, even though the domain name has been formally phased out.
The organization that coordinates all that is the Internet Corporation for Assigned Names and Numbers, or ICANN, a California-based non-profit that gets its authority from the US government, which funded much of the Internets early development.
In 1998, ICANN took over a naming system created in the 1980s by the Internets core engineers.
(While ICANN sets policies and assigns names, subject to Commerce Department oversight, VeriSign runs the main directory computers under a contract. VeriSign separately keeps the lists for names registered under ".com" and ".net.")
Three of the original names ".com," ".net" and ".org" are available to anyone, although ".com" was designated for commercial entities, ".net" for network providers and ".org" for organizations.
Others are reserved: ".edu" for educational institutions; ".gov" for the US government; ".mil" for the US military and ".int" for organizations established by international treaty. In addition, ".arpa" is used internally and is rarely seen by the public.
About 250 two-letter suffixes were initially assigned to various countries, territories and the continent of Antarctica, and more recently, the Palestinian territories got ".ps" and the European Union ".eu."
These are generally based on lists kept by the International Organization for Standardi-zation, which, in turn, took information from the United Nations.
Although each country-code domain is meant for a countrys residents and businesses, some countries have tried to raise money by permitting anyone in the world to use their suffixes. So a television station anywhere can claim Tuvalus ".tv" and a doctor can use Moldovas ".md."
In 2001, ICANN approved the first expansion of the addressing system, adding seven, including ".info" for general use and ".biz" for businesses.
Others are restricted: ".aero" for the aviation industry; ".coop" for business cooperatives like credit unions; ".museum" for accredited museums worldwide; ".name" for individuals; and ".pro" for professionals. Each has its own group deciding who qualifies.
ICANN is in the midst of a second expansion, having already approved ".jobs" for the human resources community, ".travel" for the travel industry, ".mobi" targeting mobile services, and ".cat" for the Catalan language.
Others in the works include ".xxx," a controversial proposal to create a virtual red-light district for porn sites, and ".asia" for the Asia-Pacific community.
So how do you get one of these names?
Its pretty easy with the general-use suffixes like ".com" and even the specialized ones like ".travel."
ICANN has approved scores of companies to sell those names for as little as a few dollars. The list is at http://www.icann.org/registrars/accredited-list.html.
Country-code suffixes are tougher.
First, you must check whether you even qualify for one, since some are restricted to residents, and some subdivide their domains so UK businesses must use ".co.uk." Then you must find the companies that register names under that particular suffix.
A good rule of thumb is to start by going to http://www.iana.org/cctld/cctld-whois.htm and finding your countrys two-letter code.
Then, try typing "http://www.nic.xx," with "xx" representing the two-letter country code. It doesnt work with every domain, but for many of them, youll get information about that suffixs registration policies and procedures.
Keep in mind, though, that not all of these suffixes will be as reliable as ".com" and the other major ones.
Iraqs ".iq" was in limbo for years after the 2002 federal indictment of the Texas-based company that was running it on charges of funneling money to a member of the militant group Hamas.
Only in July did ICANN approve transferring the ".iq" name to Iraqs telecommunications regulator.
So what are the most popular domain names anyway?
Tops, of course, is ".com." Germanys "de" is next, followed by ".net," ".uk," and ".org."
Despite the United States having the largest Internet population, ".us" ranks 10th; most simply go for ".com" or one of the other global domains.