Abstract :
Imitation happens. Sometimes it is obvious when it happens, such as the resemblance of Internet Explorer 1.0 to Netscape Navigator 1.0. Sometimes it is vaguely in the details, such as the resemblance of the trash can in Windows to the same symbol in the Macintosh OS. A common perception is that there is more competitive imitation today than in the past. Is there truth to this perception? To understand the broader point, consider dividing the world into fast and slow imitation. We explain how each of these imitation work.