The meaning of this sentence is that you can make either pure Silverlight application and use RadMediaPlayer there, or you can have an ASP.NET Ajax application that hosts a rich Silverlight control. In our case, this the RadMediaPlayer. You can find more info here: http://msdn.microsoft.com/en-us/magazine/cc135987.aspx
There is no way to use RadMediaPlayer without Silverlight. You can encapsulate the Silverlight in aspx page.
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