Piloting an Actor in the Viewport
To Pilot a Actor in the Viewport, right-click on the Actor and choose the option from the context menu for Pilot.
Piloting is especially useful for Camera Actors and Lights.
While piloting is active, you will see the piloting text and icons in the upper left of the Viewport. This indicates that you have some Actor attached to the view.
Once piloting, you will look down the X-Axis of the given object. You may then move the view as normal and the Actor will come along automatically.
In this image, we have locked a SpotLight Actor to the view. Now, wherever we move the view, the light will follow as if attached to the Viewport's camera.