How to put mode Info into comment header of program?

[Wei]

Hi,

I am not sure if this is a trivial question. But it definitely seems
non-trivial to me.

Recently I browse some common lisp code written for Artificial
Intelligence, which can be found at 
http://aima.cs.berkeley.edu/lisp/doc/overview.html.

I think the author uses Emacs for his common lisp programming, The
interesting part is on the top of each of his lisp program, he has a
line like ";;; -*- Mode: Lisp; Syntax: Common-Lisp; -*- File:
utilities.lisp". I think this is automatic inserted through some
mechanism and could be used for other programming language mode also,
such as cc-mode.

However, I searched over goolge for quite a while and couldn't find
what kind of setting can enable this.

Can I get any hints from any of you experts?

Thanks!