Six Website Features Which Are Bad For Your SEO
All Flash Website : Difficult for spiders to crawl.While search engines have improved their ability to index text based content within flash files,excessive dependence on flash is still bad idea for both SEO & usability.
JavaScript Navigation : Spiders often don't activate java script code,so unless you implement an alternative they may struggle to reach other pages on your site via script based navigation.Make sure you have at least one regular,text based hyperlink to every page on your site.
Frames : Frames are notoriously difficult to implement effectively from a user experience perspective,are very rarely necessary,and often cause indexing problems for search engine spiders.
Image maps & other non-text navigation : Some spiders may have problems following these links.If you use image maps for navigation on your pages ,make sure you have alternative text-based hyperlinks leading to same pages.
Dynamically Generated pages : Less of a problem than it used to be, but some spiders can have trouble with very long dynamically generated urls that contain too many parameters (?W=XYZ).Try to configure your site to use "Search Engine Friendly" urls where possible or at least restrict dynamic URL parameters to a maximum of three .
Ajax : Again its Difficult for spiders to activate the code.
Always believe that words are the foundation for SEO .The starting point for effective SEO is knowing what the people who are looking for your products ,services or information are typing into the little box on the search engine homepage .Known as keywords or keywords phrases these form the foundation of your SEO Efforts.