Does the user need any special tools to use an Ajax-enabled web site?
Not really. As long as the user has a relatively recent version of any of the top browsers they should be OK. The browser list includes Internet Explorer, Firefox, Safari and others. The heart of Ajax is a browser component called the XmlHttpObject; In Internet Explorer this component is implemented as an ActiveX component while other browsers have their own mostly-compatible implementation.The XmlHttpObject is what you – the developer – use to send queries to the web server without forcing the user to reload the whole browser page. When the server responds to the request you use JavaScript to update part of the page, using the Document Object Model. It’s important to realize that each browser may have its own quirks when it comes to JavaScript and this is where Ajax development can be tricky.