Disadvantages
- The back and refresh button are rendered useless
With AJAX, as all functions are loaded on a dynamic page without the page being reloaded or more importantly a URL being changed (except for a hash symbol maybe), clicking the back or refresh button would take you to an entirely different web page or to the beginning of what your dynamic web page was processing. This is the main drawback behind AJAX but fortunately with good programming skills this issue can be fixed.
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