Games are the easiest of computer activities to translate into the language of theatre, although it is more like a television episode than a theatrical performance or movie being viewed in a large auditorium. In a theatre or movie, once the drama has begun it is difficult to leave, whereas in television, the viewer can leave at any moment, so it is important to keep people continually engaged: long explanations, background or back story information that might be necessary for the story must be disguised to maintain the audience's interest. In similar fashion a computer game must continually engage interests, for the disinterested player can easily quit. Attention must be continually maintained. This can be done even in quiet periods through anticipation as long as the player always has an expectation of future interesting engagement. Anticipation is the soul of emotion.
What about more mundane examples of computer usage? Laurel shows how even the activity of writing or composing a budget on a spreadsheet has a dynamic that permits interest to be sustained for long periods. Here, the actor is also the playwright and the spectator, so the expectations are self-generated, enabling interest to be sustained for what otherwise might be considered long, dull periods. After all, the actor/playwright/spectator is always watching to see how their self-generated drama unfolds, whether it meets expectations, whether the characters (the numerical characters in the spreadsheet) behave as expected.
Television and movie series provide yet another lesson. Some episodes might follow previous ones in periods measured in years: think of Space Wars, Star Trek, or James Bond films. These gaps require reminders to carry the viewers over the gaps. Sometimes these reminders are given through flashbacks or asides, sometimes by introducing new characters who then have to be brought up to date with the audience as eavesdropper. Similar needs for reminders exist for email interactions, checking up on friends via social networks, or even writing a homework assignment, an essay, or a book. These activities are spread out over time, with variable gaps between segments. How do we maintain continuity? One mechanism is through repeated snippets of previous conversations in social networks or email, another through ready access to previous work, and yet another though mechanisms somewhat akin to the way movies and television episodes must brief newly introduced characters. With computer systems, this can be done through active reminding and prompting.
This component of drama is usually overlooked by computer system designers. When a break in activities is caused by interruptions from competing activities, when we resume the initial task, if the playwright (that is, the programmer or system designer) does not provide reminders of the previous states and activities the result can be errors in the conduct of critical tasks. Witness errors in the use of medical systems, in aviation, and in complex activities that range from cooking a meal to controlling a complex chemical plant. Just as playwrights must help the audience bridge time gaps, the designers of systems must help computer users bridge their gaps.
Simple Rules, Emergent Outcomes
Many interface designers tend to optimize every element of an experience, but as Laurel points out, maximum enjoyment and emotional peak can only come about as a contrast to lows, disappointments, and tension. A positive