Windows presentation foundation query.

you can check here

 

https://msdn.microsoft.com/en-us/library/ms742806%28v=vs.110%29.aspx 

It's a similar concept as event bubling, but in case of routed events the event sequence move upwards from child to its parent to its parent and likewise.

 

The strucuture of WPF is like that you can have a control inside any other container control so in that case it is important to have route events so that events of one control can be handled by another.

 

This was most basic answer, for more google.