The World Wide Web employs unique numbers referred to as IP addresses and every single unit or site that is a part of the Web contains such an address. It is pretty difficult to remember to go to 123.123.123.123 to see a website though, that's why a significantly easier system was introduced in the 80s - domain names. Every domain is made of a main part plus an extension, for example domain.com or domain.co.uk. Many different extensions exist worldwide - part of them are assigned to countries, for example .co.uk in the abovementioned example, which is assigned to the United Kingdom, while many others are generic, for example .com or .net. Many extensions are available for registration by any entity and others have precise requirements - company registration, local presence, etc. You can obtain a brand new domain name from a registrar organization like ours and if the extension supports domain name transfers, you're able to transfer an existing domain between registrars too.