Actors are treated as a broad relation that holds between a given event and any existing thing that is meaningfully involved in the event. When we say that someone (or something) is an actor in an event, we're saying that someone (or something) is somehow saliently (directly or indirectly) involved in the event during the event. An object's merely being cotemporal with an event is obviously not sufficient for being an actor in it, nor is participating (however centrally) in a representation or re-enactment of the event. But note that being an "actor" is not restricted to things that play "active" (as opposed to passive or instrumental) roles in a given event. Some examples of Actor relations are: hostage, container used, project leader, product created, and primary object moving.

Actions are events that are carried out by some "doer". Actions are any event in which one or more actors effect some change in the (tangible or intangible) state of the world, typically by an expenditure of effort or energy. Note that it is not required that any tangible object be moved, changed, produced, or destroyed for an action to occur; the effects of an action might be intangible (such as a change in a bank balance or the intimidation of a subordinate). Note also that the doer of an action, though typically an agent, need not be (e.g. a falling rock that dents a car's roof). Depending upon the context, doers of actions might be animate or inanimate, conscious or nonconscious.