How to use AJAX with ASP.NET

Question

<h3 style="color: purple;"><span style="color: #800080;"><strong>I have rich expeience in asp.net<br /></strong></span><strong>but not yet tried AJAX with asp.net and MVC also<br /></strong><strong>So kindly suggest me ways for doing it<br /> </strong><span style="color: #800080;"><strong>Thanks ...&nbsp;</strong></span></h3>