October 23, 2021

A subdomain (or subdomain; English: Subdomain) is a domain belonging to a higher domain in the domain name system hierarchy. For example, and are two subdomains of, and is a subdomain of the top-level


WWW2 is the subdomain name of the shunt server in the World Wide Web. It is mainly used to identify some related websites within a domain name.,, and are examples of them. These subdomains can be extended to WWW3, WWW4, WWW5, WWW6, etc., and so on. Generally speaking, these domain names are used for server load balancing. Sometimes, even when browsing the website mirroring, these special domain names will be hidden, and the display will still be "WWW".


domain name Domain Name System Top-level domain Secondary domain

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