A top level domain represents the top level in the Domain Name System hierarchy. It is the part located at the very end of URL after the last dot. Top level domains are given by the Internet Corporation for Assigned Names and Numbers (ICANN), which is operated by the Internet Assigned Numbers Authority (IANA).
There are multiple groups of top-level domains. The most common are country-code top-level domains (ccTLD), generic top-level domains (gTLD), sponsored top-level domains (sTLD), unsponsored top-level domains and infrastructure top-level domain (.arpa).
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