Thank you Pradeep. Great information. That would certainly help others as it did to me. I would like to inform you that Please try and edit 2nd paragraph under Spiders or Crawlers. There is repetition there which makes the great article a little clumsy and remove " Meta Tag is" in the very next paragraph if you can. I would like to know about search logic of Social networking sites like Facebook or Myspace from you. because you seem to have great knowledge about search engine and their logic.

Thank you.