How to implement text output in Linux console after command?

Question

linux

I'm new to linux and would like to know how to output text or ASCII art when I type some command like:

[email protected]:~# easteregg
Hello world!

Answer 1

Fastest:
Method two:
Method three:

# Либо открываете этот файл в редакторе и пишете на любом известном вам яп
echo -e '#!/bin/bash \n echo Hello world' > /usr/local/bin/easteregg 
chmod +x /usr/local/bin/easteregg

The first will work within the shell session, the second will become permanent, but only for the current user, the third will be available to everyone and always, but will require root rights.
Enough for now?:)