Kendo UI is a pure client-side library built on top of jQuery (i.e., jQuery widgets)
UI for ASP.NET MVC are server-side MVC wrappers for Kendo UI (i.e., they result in Kendo UI widgets being instantiated on the client-side while you write Razor).
UI for ASP.NET AJAX is mostly IScriptControl WebForms controls based on MS AJAX. It also contains a few wrappers for Kendo UI widgets.
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