Robots.txt for your website ?

[bob]

Web site owners use the /robots.txt file to give instructions about their site to web robots; this is called The Robots Exclusion Protocol.

 

[suzykenedy]

Robots.txt is a text file you put on your site to tell search robots which pages you would like them not to visit. Robots.txt is by no means mandatory for search engines but generally search engines obey what they are asked not to do. It is important to clarify that robots.txt is not a way from preventing search engines from crawling your site.