A friend asked me this question & this is my attempt at answering it. A country code top-level domain (ccTLD) is an Internet top-level domain (like .com, .net, .org) generally used or reserved for a country, a sovereign state, or a dependent territory. Internet Assigned Numbers Authority (IANA) is responsible for determining an appropriate trustee for each ccTLD. Each country's trustee may assign registrars to sell domain names with suffixes pertaining to their country as per their policies. A country code second-level domain (ccSLD ) is a second-level domain to a country code top-level domain. Some domain name registries introduce a second-level hierarchy to a TLD that indicates the type of organization intended to register an SLD under it. For example, in the .uk namespace a college or other academic institution would register under the .ac.uk ccSLD, while companies would register under .co.uk. The complete list of suffixes including those for each country are avai...