Pablo Moyano:
In section "Editorial Note" under "Abstract", it says This is revision $Id: Overview.html,v 1.119 2012-02-20 18:29:29 arangana Exp $. i think the "$id" is a programming error of this webpage
No, it's just an automatically inserted CVS $Id$ tag listing the revision of the file.
http://www.fluidthoughts.com/howto/cvs/keywords/
