Web hosting services, on the other hand, run servers that are typically assigned only one or a few addresses while serving websites for many domains, a technique referred to as virtual web hosting. Such IP address overloading requires that each request identifies the domain name being referenced, for instance by using the HTTP request header field Host:, or Server Name Indication.

ICANN publishes the complete list of TLD registries and domain name registrars. Registrant information associated with domain names is maintained in an online database accessible with the WHOIS protocol. For most of the 250 country code top-level domains (ccTLDs), the domain registries maintain the WHOIS (Registrant, name servers, expiration dates, etc.) information.

Domain names are often simply referred to as domains and domain name registrants are frequently referred to as domain owners, although domain name registration with a registrar does not confer any legal ownership of the domain name, only an exclusive right of use for a particular duration of time. The use of domain names in commerce may subject them to trademark law.

A few companies have offered low-cost, below-cost or even free domain registration with a variety of models adopted to recoup the costs to the provider. These usually require that domains be hosted on their website within a framework or portal that includes advertising wrapped around the domain holder's content, revenue from which allows the provider to recoup the costs. Domain registrations were free of charge when the DNS was new. A domain holder may provide infinite number of subdomains in their domain. For example, the owner of example.org could provide subdomains such as foo.example.org and foo.bar.example.org to interested parties.
ICANN renewed Verisign’s .com contract, this time with an interesting new clause — the $6 cap previously placed on Verisign’s fee was removed, granting permission for Verisign to raise their fee by 7% each year from 2007 to 2010, bringing it to $7.85. The justification given by ICANN was “to allow market forces to determine prices”, which I don’t quite follow, but I’m no Keynes. They also point out, in subtler language, that it’s the US government’s job to worry about Verisign’s monopoly, which is, I guess, fair.

Keep in mind that these are the highest value cash only sales that have been reported to us in the past week. This column is meant to be an educational tool, not a complete list documenting ALL high value domain sales. Such a list is impossible to produce because many sales are kept private at the insistence of buyers, sellers or both. Our procedure for verifying the accuracy of domain sales reports is available here.
Getting a domain name involves registering the name you want with an organisation called ICANN through a domain name registrar. For example, if you choose a name like "example.com", you will have to go to a registrar, pay a registration fee that costs around US$10 to US$35 for that name. That will give you the right to the name for a year, and you will have to renew it annually for (usually) the same amount per annum.
A domain name consists of one or more labels, each of which is formed from the set of ASCII letters, digits, and hyphens (a-z, A-Z, 0-9, -), but not starting or ending with a hyphen. The labels are case-insensitive; for example, 'label' is equivalent to 'Label' or 'LABEL'. In the textual representation of a domain name, the labels are separated by a full stop (period).
If you're having trouble finding a domain name (whether because of crowding or cyber-squatters), check for a help facility on each registrar's site. Domain registrars typically house search engines that return a listing of available names similar to the one you want. When you search for a domain name at Namecheap, for example, you get both the status of that name and a list of suffixes available for that name. Maybe [Sitename].com isn't available, but [Sitename].biz or .org is.
Registrars offer a wide variety of registration durations—one year, three, five, and even ten. Be careful about registering for more than a year, though. First, there might be restrictions on your ability to transfer the domain name should the registrar give poor service. Second, the registrar could go out of business, leaving your domain name without a host. Check the policies closely.
There are tons of great domain names available for registration and it can take as little as five minutes to register one at any domain name retailer. These online stores make it very easy for you to search for available domain names with name suggestion tools. They also offer complementary services, such as Web hosting and website design so you can register your desired domain name and set up a website all at once.
Domain Privacy prevents these spammers from collecting your personal info. DreamHost’s complementary (yes it’s free for the life of your domain) Domain Privacy service works by masksing your personal information in the WHOIS database with DreamHost’s corporate information, so you’re protected from unscrupulous marketers, spammers, robo-callers, junk mailers, and stalkers.
Even when you register and pay for your domain name, you won't necessarily be able to use the name for several hours or even a few days. The domain must propagate, meaning that the official domain name registry must be updated with your website's Domain Name System information. That's something that occurs on the backend without any need of input from you.

FatCow has one of the cheapest offers for an entire website package, with hosting and domain names for just thirty cents during your first month. After, that the price is $10.99 a month or $59.88 for the whole year, in a shared hosting package with enough bandwidth for most people. This is a limited promotion I found, but they still sell fairly well-priced packages (their "fat" options come with extras like marketing and advertising credits), and will gladly offer you perks for transferring your domains and hosting to them.

An important function of domain names is to provide easily recognizable and memorizable names to numerically addressed Internet resources. This abstraction allows any resource to be moved to a different physical location in the address topology of the network, globally or locally in an intranet. Such a move usually requires changing the IP address of a resource and the corresponding translation of this IP address to and from its domain name.