What is a top-level domain name (TLDN)?

This is the highest level in a domain hierarchy of a fully-qualified domain name, like .com, .net, .org, etc.
ICANN.
Internet Corporation for Assigned Names and Numbers, is the body that controls adding of new TLDNs.
You can read more about it here http://en.wikipedia.org/wiki/Tld

Top-level domain (TLD) refers to the last segment of a domain name, or the part that follows immediately after the "dot" symbol. TLDs are mainly classified into two categories: generic TLDs and country-specific TLDs. Examples of some of the popular TLDs include .com, .org, .net, .gov, .biz and .edu. Check this out for getting more info...

A "Top Level Domain" is what comes after the last dot in a Domain Name. Or, to put another way, what is to the ‘right” of the final dot.Some of the most commonly known Top Level Domains are: .com, .net, and .org and .au.

 

The Top Level Domain types such as .com, .net and .org have been around for many years (since the Internet took its current form). Most of the possible (and comprehensible) Domain Names have been allocated from these TLDs.

 

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