To get deeper with what the routed events are and how RadControls for Silverlight uses them, Telerik prepared a new training session on Silverlight routed events.
With the Windows Presentation Foundation a new type of events were introduced - the Routed Events. They have provided the developer with an entirely new approach to the eventing and the event handling. Basically, Routed Events traverse the logical tree upwards or downwards, depending on their Routing Strategy – Bubble and Tunnel respectively.