How to tell if a site is using Ajax and why you should care

From an SEO perspective, you need to understand how a site operates in order to better optimise it for the search engine crawlers. Ajax generated contents online are largely not indexed by the search engines, and although this is likely to change in the future, the use of Ajax to generate content that is intended to be indexed by the search engines is not recommended at present − this is a classic example of search engines holding back the progress of the web.