These are entirely different files. Robots.txt - This tells the Search engines which URLs should not be indexed. .htaccess - This file can achieve many functions, such as - Ban a particular IP or User-agent. - Redirect URLs - Rewrite URLs with SE friendly names etc
robots.txt tells search bot to not index parts .htacess forces search bots to not visit some areas so they cant index
Ok How to tell search bots not to index my proxified pages and how effective it is after immediately placing robots.txt in the server.