The action area indicates where the action takes place in a frame. In the Topic Editor, it is designated by a red rectangle overlaying the frame's screenshot.
You may find that you need more than one action area to accommodate an action on a particular frame. For example, if you are recording the action of clicking the Home button in a browser and two screen elements (toolbar and navigation bar) contain the Home button, you could have an action area for each button.
To create a new action area for the current frame: