ASP.NET

ASP.NET AJAX is the free Microsoft AJAX framework for building highly interactive and responsive web applications that work across all popular browsers. The ASP.NET AJAX framework includes Server-Side ASP.NET AJAX, Client-Side ASP.NET AJAX, the AJAX Control Toolkit, and the jQuery library. ASP.NET AJAX enables developers to choose their preferred method of AJAX development, whether it is server-side programming, client-side programming, or a combination of both.

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