The very first time someone uses a computer, a software application or anything else for that matter. Everyone is a first-time user when they are confronted with the user interface in an app or a control panel on a home appliance or even a new car. In fact, if you never read a particular definition in this encyclopedia before, you are a first-time user whenever you do read it. If the explanation was clear, our goal was met; namely that it makes sense without having to re-read it several times. See good user interface and user interface.