Difference between EventHelper and ScreenSpaceEventHandler

I was dealing with event handler and used ScreenSpaceEventHandler for my case. Afterwards I found the EventHelper, however, there is not a sample to explain the use of them.
I am wondering what is the difference between these two event handler and if anyone, please give me some examples on how to use them.

EventHelper has nothing to do with ScreenSpaceEventHandler. EventHelper is simply a utility class for easily unsubscribing to a bunch of previously subscribed event. ScreenSpaceEventHandler

Sorry, hit send by accident. I meant to add “while ScreenSpaceEventHandler is for dealing with device input”.