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. The Internet Corporation for Assigned Names and Numbers (ICANN), is the entity that coordinates domains and IP addresses for the internet.