localhost (127.0.0.1) @ OS

Bind any domain name(s) to this loopback per hosts file declaration(s).

127.0.0.1       foo.com
#::1            foo.com

127.0.0.1       google.com
#::1            google.com

127.0.0.1       big.bar.yo
#::1            big.bar.yo

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.
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Redirects any domain name, whether real (existing IP per public DNS) or not.

hosts File location:

• Win10 :: C:\Windows\System32\drivers\etc\hosts
  • Edit per hosts.bat (@ CMD terminal).
• Linux :: /etc/hosts