127.0.0.1

Question

Why is this IP address sacrosanct ?

Answer 1

Everyone has it own name;
In networking term we have every machine name
127.0.0.1
If you want to send any message on your own ip then use this.
It reserved for local Machine ip

Answer 2

It's IP of localserver.

Every computer has its own local server.
It's IP is 127.0.0.1 and default hostname is localhost.

Answer 3

It is called a loop back IP address.