If you want to develop your website with great Search Engine Optimisation, or SEO, in mind there is a rule to bear in mind for the use of Frames, Flash and Ajax.
The rule is: don’t use Frames, Flash or Ajax.
While Frames, Flash and Ajax do the jobs that they are supposed to, they don’t do anything to help improve your search engine ranking, in fact they actually hinder your chances of improving it.
One of the reasons for this is that search engines require text based content in order to discover a page and rank it. A website designed entirely using Flash might look great and work like a charm, but the crawlers sent out by the search engines simply cannot read it because they require text and not images to recognise. On the surface the site may be very functional and impressive but as far as the search engines are concerned none of this great Flash content exists.
Another reason is that Frames, Flash and Ajax make it impossible to link back to single page or particular element within. This renders it impossible to attempt to improve your search rankings for a particular page within the site. This could ultimately be the difference between SEO success and failure.
It also means that people landing on your site in search of a particular element would have to find it for themselves and in many cases don’t tend to be incredibly patient in doing so.
It is not recommended that you use Frames at all, when designing your site, and if you insist on using Flash or Ajax, we’d recommend you use it sparingly. They might be great tools, but represent an obstacle to good SEO, rather than a benefit.