Domain Name Servers translate domain names into IP addresses.
Internet addresses (IP numbers) are extremely difficult to remember. In the "good old days" you needed to look up IP numbers in tables to discover a particular server's IP number. Domain names help resolve this issue by using aliases for IP addresses. For example, the domain name gla.ac.uk currently is an alias for the IP address 22.214.171.124
ICANN is responsible for issuing the top level domain names. These include generic categories and country names.
Most top level country domains issue a range of sub-domains based on categories simlar to the top level category domains. Individuals or organisations can register domain names within these sub domains.
Non profit organisations
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