Some methods of optimizing a site's searchability used which are frowned upon by search engines are:

• Listing of Bogus keywords: Many webmasters have included words in their keyword list that have absolutely nothing to do with their website. This is a feeble attempt to make their URL appear more frequently in a search results regardless of the search criteria. I list this first because this is what search engine frown upon the most!
  
  i.e. If you did a search for "Used Cars" and the search engine gave you a link to a website that sells only fishing tackle, wouldn't you get a little upset at the search engine? You weren't searching for fishing tackle!!! But if the owner of the fishing tackle website put "Used Cars" in his keyword list, then this could possibly happen, and the search engine gets blamed for inaccurate search results.



• Submitting a URL more than once: Webmasters have cleverly tried to fool search engines by sumitting their URL to the same search engine more than once. They try to make the search engine see the same URL as two different URL's by submitting it in different formats such as:
  http://www.somesite.com & http://www.somesite.com/index.html


• Repetative use of keywords: Some search engines rank search results according to the frequency that a particular search-word is used within the whole HTML document (webpage). Therefore, webmasters will copy and paste the same word over and over in their keyword list.


• Hidden List in Page Body: For search engines that parse page-content as well as keyword lists, webmasters have tried to put additional keyword lists in the body of the webpages. Since their keyword lists are not intended to be a visible part of the page, feeble attempts have been made to hide the list, such as makeing the text color the same as the background color, or "commenting out" the list.

All these techiniques are frowned upon because they are all misleading! Many search engines are cracking down on the techniques listed above. Usually if a search engine discovers that a particular website is using one or more of the techniques listed above, the site will be "blacklisted", meaning that the search engine will cease to list that website's URL when displaying search results to their users.

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