Below are examples for best practices that have been set aside specifically for writing documentation, fictional stories, source code, or anything else where an example needs to be given without the fear of resolving to an actual phone number, domain, website, etc.
In 1999, the "example.com" domains have been set aside by the IETF in RFC 2606 and updated in RFC 6761 specifically for documentation and source code. They include example.com, example.net, and example.org. The example.edu domain was added by ICANN in 2000. Later, the ".example" top-level domain name has since been added explicitly for documentation purposes. While the pseudo-top-level domain ".local" carries no meaning, it is commonly deployed in multicast DNS, local DNS, and private networks. While it too could be used for documentation, it's better left alone, and to use the "example.com" and ".example" domains.
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