I believe SMTP uses “HELO”, actually (or “EHLO” to enable some extensions). The server then indicates that it heard the HELO command, often with a cheery remark like “Pleased to meet you! I’m a server! :-D”
This is one of the more charming aspects of the internet’s plumbing.
There are actual plain text protocols (e.g. SMTP) that do use “HI” for initiating communication.
I believe SMTP uses “HELO”, actually (or “EHLO” to enable some extensions). The server then indicates that it heard the HELO command, often with a cheery remark like “Pleased to meet you! I’m a server! :-D”
This is one of the more charming aspects of the internet’s plumbing.