Case Study 1: Here Come the Teletubbies

The Teletubbies are four fantasy characters whose television adventures appeal to children ranging in age from less than a year old up to ages threeor four. The Teletubbies are playful and childlike technological toddlers, and their behavior is deliberately meant to invoke feelings of identification from children. As characters, the Teletubbies have two specific idiosyncrasies that must be accommodated in any interface mimicking their behavior. First, their use of language is very limited. Their speech is restricted to one- or two-word utterances that sound very much like "baby talk," the immature speech of one-and two-year-old children themselves. What the program lacks in dialog, however, it makes up for with a rich nonverbal aural environment. The Teletubbies program is filled with music and dramatic, larger-than-life sound effects of different kinds. The use of music and vivid sounds in the character's interface along with speech raised troubling questions: Would it confuse children?

The second essential feature of the Teletubbies characters important to the interface is physical: The Teletubbies each have a television screen in their tummies. The tummy screen...