Create multiple files with different extensions with one command
Something like
touch index.{js,css,html}

should work. Which of course can then be turned into a shell function with
miracle() {
    [[ &quot;$1&quot; ]] &amp;&amp; touch -- &quot;$1.&quot;{js,css,html}
}

The test ensures that the files only get created if a name is passed as an argument, the touch -- ensures that miracle -foo doesn't lead to an error.
and used as
miracle index

To have this defined automatically in bash add the function definition to ~/.bash_profile, for zsh use ~/.zprofile.