standard for robot exclusion definition World-Wide Web
A proposal to try to prevent the havoc wreaked by many of the early World-Wide Web robots
when they retrieved documents too rapidly or retrieved documents that had side effects (such as voting). The proposed standard for robot exclusion offers a solution to these problems in the form of a file called "robots.txt" placed in the document root of the web site
W3C standard (http://w3.org/TR/html4/appendix/notes.html#h-B.4.1.1).