In this essay, we will explore the idea of emergence. We will examine how objects and patterns can arise from simple interactions in ways that are surprising and counter-intuitive. We will present examples with simple squares that turn on and off, but the underlying ideas will provide you with a new perspective for thinking about many phenomena in the everyday world. —Resnick and Silverman —Exploring Emergence (Life-Long Kindergarten — MIT)

An interesting series of short web pages, each with a JavaScript box that demonstrates a concept from Life (a game in which a set of simple rules turns on and off blocks on the screen). Created in 1996.