Top Level Domains (TLDs)
The domain name structure is defined in RFC 1591
See: ICANN TLDs
"country-code" TLDs or "ccTLDs"  (such as .de, .mx, and .jp) 
"generic" TLDs, or "gTLDs"
 1980's .com, .edu, .gov, .int, .mil, .net, and .org
 (Old: .arpa, .nato)

Domains:
Top level Domains (TLD)
Original (198?):
.com	Commercial
.gov	Goverment
.org	Organization
.net	Network
.edu	US Educational
.mil	US Military
.int	organizations established by international treaties between governments. 
 Nov 2000

Country Code Names:
.au - Australia, .ca - Canada, .gb - United Kingdom (Great Britain),
 .de - Germany, .fr - France, .tw - Taiwan, .us - United States, ...
Complete list of Country Code Elements

New:
.biz (2001)	Businesses	
.info	(2001) Unrestricted use	
.museum	Museums	
.name	(2002) For registration by individuals	
.bz
certain country-code top-level domains (ccTLDs) have decided to open their name spaces
 to all interested registrants, regardless of country.
  These domains are often referred to as "open ccTLDs"
.cc (Cocos Islands)
.tv (Tuvalu) - Television
.ws (Western Samoa) - Web sites

Proposed:
.aero - Air-transport industry
.coop	Cooperatives	
.pro	Accountants (cpa.pro), lawyers (law.pro) , and physicians (med.pro)
In 2013 and 2014 over 200  new top-level domains were opened.
e.g.  .church, .consulting, .careers, .ventures, .singles, .bike, .guru, .camera, ...
As of October 2014 there were 735 active top-level domains.

Review/Ratings of Registration Services:
www.webHostingRatings.com
ConsumeRsearch.com/domain-registration

Domain Registries: by volume
1. Go Daddy (www.GoDaddy.com)
2. namecheap.com
3. www.dotster.com
4. 1and1.com
5. www.NetworkSolutions.com
The following were ranked #2 and 3 in 2012
eNom - domain name, web site hosting, email, registration
Tucows Domains 
www.register.com
Register.com
Name.com
Domain Names  | Uniregistry

Blogger.com and WordPress.com will provide you with a sub-domain name, which looks like yourwebsite.blogspot.com.

WhoIs domain owner lookup AllWhoIs
WhoIs Lookup at Network Solutions
www.nic.name/getname
Gandi.net whoIs
tucows WHOIS Lookup Utility

DNSstuff.com ________________________

	
Assignment/Administration
The Internet Corporation for Assigned Names and Numbers (ICANN)
List of Accredited Registrars 
Top level Domains (TLD) at (IANA) Internet Assigned Numbers Authority
Network Solutions a VeriSign Company
Verio Register Domain Names
_______________________________________________________
Geographic:
  See examples on the Matching Domains and IP Addresses Page
US and Canada:
  .ST.CC    (State/Province.Country)
  e.g. .qc.ca (Quebec)

US Domain is defined in RFC 1480
     .FED.US          Federal Government
     .DNI.US          Distributed National Institutes
     .ISA.US          Interstate Authority
     <city>.<state>.US   <state> is the 2 digit state postal code
     <county>.<state>.US
   .CI.<city>.<state>.US   City Govt
   .CO.<county>.<state>.US County Govt.
  .CC.<state>.US           Community College
  .TEC.<state>.US          Technical and Vocational Schools
  .K12.<state>.US          K-12 Schools
  .PVT.K12.<state>.US      Private Schools
  .state.<state>.US        State Government
  .lib.<state>.US          Libraries
  .MUS.<state>.US          Museums
  .D<state>.ST.US          Districts
  .COG.<state>.US          Councils of Government
  .GEN.<state>.US          General 

International:

  .com.CC    (where CC = 2-digit country code)
  .edu.CC,  .or.CC,  .org.CC,  .net.CC,  .ac.CC,  .co.CC,  .go.CC,  .re.CC,
    .plc.uk,  .ltd.uk,  .cnet.fr,  .eunet.CC  (EuropeNet)
  You may also have just <company>.cc (e.g. ericsson.se, nortel.ca)
  
W3 Servers by Continent
DXCC Country list


Terms:
ccTLD – Country Code Top-Level Domains
DNS - Domain Name Server
DNSSEC - Domain Name System Security Extensions
gTLD – Generic Top-Level Domain
ICANN - Internet Corporation for Assigned Names and Numbers
for internationalized domain names (IDN)
RRA - Registry-Registrar Agreement
SLD - Second-level domain
sTLD – Sponsored Top-Level Domains
TLD - Top Level Domain
uTLD – Unsponsored Top-Level Domains


See Also:
   TLD (gTLD, sTLD, uTLD, ccTLD) | Domain Name Basics | iGoldrush
   An important lesson in pre-ordering new top level domain names 
   | Domain Name Wire | Domain Name News & Views
   Matching Company, Domains & IP Addrs
   Net Names Registration Services in England
   Internet Assigned Numbers Authority
   Internet Network Information Center (InterNIC)
   Asia Pacific Network Information Center (APNIC)
   Réseaux IP Européens (RIPE)
   NORID (Norsk Registreringstjeneste for Internett Domenenavn)
       has pointers to TLD administrators around the world.
       
       

Domain Registries - Comments - Forums:
I, Cringely Which domain registrar is best? - I, Cringely

The final straw for me with GoDaddy, though, was that I let a domain lapse
 but later changed my mind and wanted to renew it. It was still held by GoDaddy 
 and the WHOIS showed it still registered to me, yet GoDaddy wanted something
  like $100 for me to get my domain back.

_____________________________________________
From:	huitema @ bellcore.com (Christian Huitema) @ smtp2
Date:	05/07/97 05:46:58 PM
Subject:	Re: IP address to domain mapping

The Internic service gives information on network registration. It is
a heavy weigt service, but you can certainly use it for the most
accessed entries.  Example:
$ whois -h rs.internic.net 206.103.249.0
Infinite Systems (NETBLK-MCI-NETBLK-INFINET-2) MCI-NETBLK-INFINET-2
                                     206.103.240.0 - 206.103.255.0
MCI Internet Services (NETBLK-MCI-NETBLK06) MCI-NETBLK06
                                      206.96.0.0 - 206.103.255.255

To single out one record, look it up with "!xxx", where xxx is the
handle, shown in parenthesis following the name, which comes first.

The InterNIC Registration Services Host contains ONLY Internet Information
(Networks, ASN's, Domains, and POC's).
Please use the whois server at nic.ddn.mil for MILNET Information.
$ whois -h rs.internic.net "!NETBLK-MCI-NETBLK-INFINET-2"
Infinite Systems (NETBLK-MCI-NETBLK-INFINET-2)
   274 Marconi Drive
   Columbus, OH 43215
   US

   Netname: MCI-NETBLK-INFINET-2
   Netblock: 206.103.240.0 - 206.103.255.0

   Coordinator:
      Nugen, James  (JN11)  hostmaster@INFINET.COM
      6142412990

   Record last updated on 20-Nov-96.
   Database last updated on 5-May-97 06:01:19 EDT.

The InterNIC Registration Services Host contains ONLY Internet Information
(Networks, ASN's, Domains, and POC's).
Please use the whois server at nic.ddn.mil for MILNET Information.


Hope this helps.

-- 
Christian Huitema
_____________________________________________
From:	huitema @ bellcore.com (Christian Huitema) 
Date:	05/15/97 02:06:31 PM
Subject:Re: IP address to domain mapping

There were plans to have .int managed by the ITU, but it may still be
managed by ISI.
The European domains are managed by the RIPE NCC (try whois.ripe.net).
The Asian domain are managed by the AP NIC.

-- 
Christian Huitema
_____________________________________________
From:	nlj @ bellcore.com ("Nicholas Lordi Jr") @ smtp2
Date:	05/15/97 08:55:47 AM
Subject:RE:  international registries

For Asia/Far East the registry is APNIC
 whois -h whois.apnic.net