Coloring Outside the Lines

In the mid-1980s, the first set of TLDs was created by the Internet Corporation for Assigned Names and Numbers (ICANN). The initial group was .com, .edu, .gov, .mil, .net, and .org, with .mil restricted to the US military, .gov restricted to Federal, state, and local US government, and a desire to limit the others to the organizations indicated by the word from which the TLD came, with the additional caveat that .edu be post-secondary institutions.

That isn’t exactly how it worked out in practice. Early registrants skirted the parameters of .edu, and although .gov, and .mil were strictly enforced, people pretty much did as they pleased with .com, .net, and .org. The most popular TLD became .com, which was the quickest to fill up, and people began to speak about a domain name shortage. In November, 1988, .int, another gTLD was introduced for international organizations that were established by treaty, but this was not sufficient.

Seven More

It was not until 2001–2004 that the next group of seven new gTLDs was introduced by the ICANN, beginning with .biz and .info in 2001. Three of the new gTLDs are sponsored, while four are unsponsored. In addition, all of the sponsored domains are restricted, as are two of the unsponsored domains. They are as follows:

And Another Six

Even before all of the seven added gTLDs were fully operational, ICANN opened consideration for additional sponsored TLDs (sTLDs). As a result of this process, five new TLDs are currently in operation, one—.xxx, which was considered for designating sexually explicit sites—was first approved and then had its approval was revoked, and .tel is due to go live in the second quarter of 2008. The gTLD .mail is still being considered.

cTLDs

Country code TLDs (cTLDs according to ICANN, but widely referred to as ccTLDs), are intended to be used only by countries and dependent territories. They are nearly all based on the ISO 3166 country codes and were instituted by ICANN. Nevertheless, some of the abbreviations are attractive to certain groups, who have created what are called vanity cTLDs, taking advantage, in some cases, of lax registration practices.

Perhaps the most famous example of this type of unapproved use is del.icio.us, a social bookmarking site founded by Joshua Schacter in 2003 and acquired by Yahoo! in 2005, that makes use of the United States cTLD in spelling delicious.

Vanity cTLDs

Other cTLDs are considered desirable in a domain name because the two letters match an established abbreviation.