The Look-at Transform node can be used to force an object to always orient itself to the location of the Look-at Transform node (figure 1). This node is typically attached to the Transform pin on a camera.
Figure 1: The Look-at Transform node attached to a geometric primitive's Transform pin
Position - The position of the node in space.
Target - The position in space the object looks at.
Up-Vector - Defines the up vector of the object.
Invert - Inverts the direction of the view vector.