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Interesting facts - Did you know?

The first commercial Internet domain name, in the TLD com, was registered on 15 March 1985 in the name by Symbolics Inc., a computer systems firm in Cambridge, Massachusetts.

By 1992, fewer than 15,000 com domains had been registered.

In the first quarter of 2015, 294 million domain names had been registered.

Most expensive domain names

Here's a list of the most expensive domain names. This is a list of domain names that sold for $3 million USD or more. The list is limited to pure domain name and cash-only sales. Sales which included website content or which involved equity deals are not listed.

Administration and Organisation of Domain Names

The right to use a domain name is delegated by domain name registrars, which are accredited by the Internet Corporation for Assigned Names and Numbers (ICANN), the organization charged with overseeing the name and number systems of the Internet. In addition to ICANN, each top-level domain (TLD) is maintained and serviced technically by an administrative organization operating a registry. A registry is responsible for maintaining the database of names registered within the TLD it administers. The registry receives registration information from each domain name registrar authorized to assign names in the corresponding TLD and publishes the information using a special service, the WHOIS protocol.

Domain name syntax

A domain name consists of one or more parts, technically called labels, that are conventionally concatenated, and delimited by dots, such as

  • The right-most label conveys the top-level domain; for example, the domain name belongs to the top-level domain com.
  • The hierarchy of domains descends from the right to the left label in the name; each label to the left specifies a subdivision, or subdomain of the domain to the right. For example: the label example specifies a node as a subdomain of the com domain, and www is a label to create, a subdomain of Each label may contain from 1 to 63 octets. The empty label is reserved for the root node and when fully qualified is expressed as the empty label terminated by a dot. The full domain name may not exceed a total length of 253 ASCII characters in its textual representation. Thus, when using a single character per label, the limit is 127