Types of domain

There are mainly 2 types of domains: general top level domain (gTLD) and country code top level domain (ccTLD).

There were just 7 gTLDs (Generic Top Level Domain) in the beginning, with .com being the earliest one. USA has been the origin of Internet, and people in the very beginning distinguish domains by uses, not by countries.

Domain Meaning and application Registry
.com Abbreviation of “commercial”, and the most popular domain in the world. Originally designated for commercial institutes yet any people could register for this domain. There are over 50M users and available domains have become scarce Verisign
.net A short form of “network”, originally used by network institutes but everyone is eligible to register for it. It’s the second most popular domain just behind .com  , with over 30M users Verisign
.org org is the abbreviation of organization, which stands for non-profit organizations. Everyone can register Public Interest Registry
.gov Only available for government institutes – mainly the US government and its affiliates. Some departments of the government in other countries also use it General Services Administration
.edu Education institutes. No institutes are able to register for it other than top tier academies in USA Educause
.mil mil stands for US Military, and is used by military institutes and their affiliates in USA Defense Information Systems Agency
.int Normally used by international organizations and sometimes NGOs of the United Nations. Not everyone can register IANA

As the Internet continued to develop, the demand for domains have been growing. ICANN has since been adding more gTLDs, making a total of 11. Some people call them “new TLDs”:-

Domain Meaning and application Registry
.aero Top level domain air-transport industry. Only those in various categories of air-travel-related entities may register SITA INC B.V
.biz Abbreviation of “businesses”. This TLD was created to provide relief for the .com TLD, where many names have already been taken Neu Level
.cat Designated to promote Catalan language and culture. Registration is open to personal, institutional and corporation websites in Catalan language or related to Catalan culture Associacio puntCAT
.coop .coop TLD only accept websites of cooperatives, collective farms and commercial organizations with cooperation. Those didn’t meet the principles of cooperatives cannot register OSG Co-op Domains Ltd
.info Became available since 2001, the first choice for network information service websites, with a view to channel the pressure of .com as well. Everyone can register Afilias Limited
.jobs Appeared since April 2005, employers could use this TLD for websites with employment information. Companies are eligible to register Employ Media LLC
.mobi Launched in September 2006, the registered websites must be used for mobile-compatible sites in accordance with standards mTLD
.museum Began in November 2000 designated for legitimate museums verified by a 3rd party. Professional organizations only Museum Domain Management Association
.name Available from November 2000, it is an Open TLD that any person or entity is permitted to register Global Name Registry
.pro Emerged in 2002, .pro TLDs are designated for professionals like lawyers, doctors and accountants. A professional certificate must be presented upon registration, and it is arguable the strictest registration requirement of all domains. Its registration fee could be as high as 10 times compared to other domains Registry Pro
.travel Made public since the end of 2005, registrants must be verified as a legitimate travel-related entity. Unavailable for personal sites Tralliance Corporation


ccTLD, aka country domain or country code TLD, has a total of 250 TLDs representing different countries or regions. ccTLDs are made up of 2 alphabets, like hk – Hong Kong, cn – China, jp – Japan, and uk – United Kingdom. These TLDs are managed by the country’s government. In Hong Kong, the .hk domain is managed by HKDNR, a government authorized institute.

To enter the Internet system, each country would apply its own ccTLD through ICANN. Some of the ccTLDs were promoted to gTLDs, such as .cc – an officially authorized domain for Cocos (Keeling) Island, Australia – being widely registered by corporations for it is the initial of “commercial company”. This happeded because many companies couldn’t register a desired .com domain. Another unconventional example is .tv, which belongs to Tuvalu. As TV stands for television and all kinds of media and video, more and more TV broadcasters and media registered for this ccTLD, earning this Pacific Ocean country an expected flow on income. Similar cases could be found in .ws (could be initials of “website”) and .sh (“shop” or “Shanghai”), providing an interesting source of income for countries with these ccTLDs.

As ICANN only plays a consulting role in ccTLD, that means each country/region can have its own presentation of ccTLD. Hong Kong, for instance, has .com.hk / .net.hk / .org.hk / .edu.hk according to TLDs, while United Kingdom has .co.uk , Japan has .co.jp , and .co.kr for South Korea. So when you want to visit Yahoo UK or Yahoo Japan, remember not to enter yahoo.com.uk or yahoo.com.jp !


代號 = 國家/地區 代號 = 國家/地區
ad = Andorra
ae = UAE
af = Afghanistan
ag = Antigua
ai = Anguilla
al = Albania
am = Armenia
an = Netherlands Antilles
ao = Angola
aq = Antarctica
ar = Argentina
as = American Samoa
at = Austria
au = Australia
aw = Aruba
az = Azerbaijan
ba = Bosnia and Herzegovina
bb = Barbados
bd = Bangladesh
be = Belgium
bf = Burkina Faso
bg = Bulgaria
bh = Bahrain
bi = Burundi
bj = Benin
bm = Bermuda
bn = Brunei
bo = Bolivia
br = Brazil
bs = The Bahamas
bt = Bhutan
bv = Bouvet Island
bw = Botswana
by = Belarus
bz = Belize
ca = Canada
cc = Cocos (Keeling) Island
cf = Republic of Central Africa
cg = Congo
ch = Switzerland
ci = Côte d’Ivoire
ck = Cook Islands
cl = Chile
cm = Cameroon
cn = China
co = Colombia
cr = Costa Rica
cs = Former Czechoslovakia
cu = Cuba
cv = Cape Verde
cx = Christmas Island
cy = Cyprus
cz = Czech Republic
de = Germany
dj = Djibouti
dk = Denmark
dm = Dominica
do = República Dominicana
dz = Algeria
ec = Ecuador
ee = Estonia
eg = Egypt
eh = Western Sahara
es = Spain
et = Ethiopia
fi = Finland
fj = Fiji
fk = Falkland Islands
fm = Micronesia
fo = Faroe Islands
fr = France
ga = Gabon
gd = Grenada
ge = Gerogia
gf = French Guiana
gh = Ghana
gi = Gibraltar
gl = Greenland
gm = The Gambia
gn = Guinea
gp = Guadeloupe
gq = Equatorial Guinea
gr = Greece
gs = South Georgia and the South Sandwich Islands
gt = Guatemala
gu = Guam
gw = Guinea-Bissau
gy = Guyana
hk = Hong Kong
hm = Heard Island and McDonald Islands
hn = Honduras
hr = Croatia
ht = Haiti
hu = Hungary
id = Indonesia
ie = Republic of Ireland
il = Israel
in = India
io = British Indian Ocean Territory
iq = Iraq
ir = Iran
is = Iceland
it = Italy
jm = Jamaica
jo = Jordan
jp = Japan
ke = Kenya
kg = Kyrgyzstan
kh = Cambodia
ki = Kiribati
km = Comoros
kn = Saint Kitts and Nevis
kp = North Korea
kr = South Korea
kw = Kuwait
ky = Cayman Islands
kz = Kazakhstan
la = Laos
lb = Lebanon
lc = Saint Lucia
li = Lichtenstein
lk = Sri Lanka
lr = Liberia
ls = Lesotho
lt = Lithuania
lu = Luxembourg
lv = Latvia
ly = Libya
ma= Morocco
mc = Monaco
md = Moldova
mg = Madagascar
mh = Marshall Islands
mk = North Macedonia
ml = Mali
mm = Myanmar
mn = Mongolia
mo = Macau
mp = Northern Mariana Islands
mq = Martinique
mr = Mauritania
ms = Montserrat
mt = Malta
mu = Mauritius
mv = Maldives
mw = Malawi
mx = Mexico
my = Malaysia
mz = Mozambique
na = Namibia
nc = New Caledonia
ne = Niger
nf = Norfolk Island
ng = Nigeria
ni = Nicaragua
nl = The Netherlands
no = Norway
np = Nepal
nr = Nauru
nu = Niue
nz = New Zealand
om = Oman
pa = Panama
pe = Peru
pf = French Polynesia
pg = Papua New Guinea
ph = The Philippines
pk = Pakistan
pl = Poland
pm = Saint Pierre and Miquelon
pn = Pitcairn Islands
pr = Puerto Rico
pt = Portugal
pw = Palau
py = Paraguay
qa = Qatar
re = Réunion
ro = Romania
ru = Russia
rw = Rwanda
sa = Saudi Arabia
sb = Solomon Islands
sc = Seychelles
sd = Sudan
se = Sweden
sg = Singapore
sh = Saint Helena
si = Slovenia
sj = Svalbard
sk = Slovakia
sl = Sierra Leone
sm = San Marino
sn = Senegal
so = Somalia
sr = Suriname
st = São Tomé and Príncipe
su = Former USSR
sv = El Salvador
sy = Syria
sz = Swaziland
tc = Turks and Caicos Islands
td = Chad
tf = French Southern and Antarctic Lands
tg = Togo
th = Thailand
tk = Tokelau
tm = Turkmenistan
tn = Tunisia
to = Tonga
tp = East Timor
tr = Turkey
tt = Trinidad and Tobago
tv = Tuvalu
tw = Taiwan
tz = Tanzania
ua = Ukraine
ug = Uganda
uk = United Kingdom
us = USA
uy = Uruguay
uz = Uzbekistan
va = Vatican City
vc = Saint Vincent and the Grenadines
ve = Venezuela
vg = British Virgin Islands
vi = United States Virgin Islands
vn = Vietnam
vu = Vanuatu
wf = Wallis and Futuna
ws = Samoa
ye = Yemen
yt = Mayotte
yu = Yugoslavia
za = South Africa
zm = Zambia
zw = Zimbabwe

Forms of doamin

Domains can be formed with 26 English alphabets (a to z, not case-sensitive), 10 Arabic numbers (0 to 9) and hyphens (“-“). Hyphens cannot be the first or last of the domain. There are different rules for different domains, like the word limit for TLDs is 67 (excluding .com , .net etc.), and Chinese domains have a work limit of 26 ( .com.cn / .net.cn / .org.cn or .gov.cn are all included).

Some might think symbols like @ / ? _ % were part of the domain, yet the fact is they are just file names:

Example Part of domain Explanation
forum.abc.com/channels/index.php abc.com /channels/index.php is the file name
info@hongkong.com hongkong.com @is not part of domain but an email address
www.-123-.com No such domain; it could only be www.1-23.com or www.12-3.com Hyphens could be unlimited, and could not be at the beginning or the end of a domain. Both a-b-c-d-e-f-g-h-i-j-k-l-m-n-o-p-q-r-s-t-u-v-w-x-y-z.com and 1-2-3-4-5-6-7-8-9-0.com are legitimate domains, but they have already been registered!

Chinese domains have emerged recently and they work as doorplates like English domains do. The domain must have at least 1 and no more than 20 Chinese characters. Both gTLD and ccTLD accept Chinese domain registrations, such as 中文.com,中文.cn,中文.hk .

Register a domain