Domain names are typically classified by their Top Level Domain (TLD) statuses. It is of utmost importance that those, interested in domaining, know the various types of domain name levels, as the resell value of domain names are mainly based on the TLD status.
There are currently three types of Top Level Domains identified by The Internet
Assigned Numbers Authority (IANA). They are:
1. ccTLDs
2. gTLDs
3. iTLDs.
ccTLD Domain Names
ccTLD’s are Country Code Top Level Domain Names. These domains are typically used by countries from around the world and their depended territories.
The registration of ccTLD domain names is often regulated in different ways by
different countries. As an example, .ws (Western Samoa) domain names can be
registered by any person around the world, while Andorran domain names (.ad) can
only be registered by Andorran nationals.
These domain names are often identifiable by their two character suffixes, e.g.:
The United Kingdom - .uk
Switzerland - .ch
South Africa - .za
The United States - .us
Germany - .de
You can find the complete list here
gTLD Domain Names
Seven gTLDs (.com, .edu, .gov, .int, .mil, .net, and .org) were created in 1980. The domain names may be registered only in .com, .net, and .org without restriction, because the other four are limited. These seven were introduced in 2001 and 2002. Just four of these TLDs (.biz, .info, .name, .pro) are unsponsored unlike the other three (.com, .net, and .org) which are sponsored. Examples of gTLD’s are typically .com, .net, .edu, .gov, .mil and .org just to mention a few.
Generally speaking, an unsponsored TLD operates under policies established by
the global Internet community directly through the ICANN process, while a
sponsored TLD is a specialized TLD that has a sponsor representing the narrower
community that is most affected by the TLD. The sponsor thus carries out
delegated policy-formulation responsibilities over many matters concerning the
TLD.
A TLD which is unsponsored operates under policies established by the global
Internet community directly through the ICANN process, while a sponsored TLD is
a specialized TLD that has a sponsor representing the narrower community that is
most affected by the TLD.
But what really is a Sponsor? This is an organization to which is designated
some defined ongoing policy-formulation authority regarding the manner in which
a particular sponsored TLD is operated. The sponsored A TLD sponsored has a
Charter, which defines the purpose for which the sponsored TLD has been created
and will be operated. The Sponsor is delegated to developing policies on the
designated topics so that the TLD is operated for the benefit of a defined group
of stakeholders, known as the Sponsored TLD Community, that are most directly
interested in the operation of the TLD.
It is also these domains that carry the highest resell value and are the most
active domain names on the trading market. Currently the world’s top domain and
most recommended is the .com, due to its resell value and nature of being in
demand.
You can find the complete list here
iTLD Domain Names
iTLDs are Infrastructure Top Level Domain Names. They are less important, less known and currently there are only two extensions we know about. They are .arpa and .root.
These domains are not open to public registration and are not seen on the
trading market in today’s practices.
The Length of Domain Names
Generally the length of domain names is restricted to 67 characters per domain name. This is a large number, and people are advised never to register domain names this length, as these domain names do not have any financial values.
The ideal length of a domain name should be around 12 letters. Due to the fact
that the majority of dictionary words in this length have already been
registered, it is not uncommon to find domain names up to 20 letters, still
carrying large value.
When one is looking to invest in domain names, the ideal name will be a short
and memorable name, easy pronounceable with little margin for typing errors.
Although these types of domains are hard to come by, and generally expensive,
they are still available on the open market.
Short domain names are not the only domains with high values. Longer domain
names can carry more value, if they are easier to remember.