Computers have dramatically altered life in the late twentieth century. Today we can draw on worldwide computer links, speeding up communications by radio, newspapers, and television. Ideas fly back and forth and circle the globe at the speed of electricity. And just around the corner lurks full-blown virtual reality, in which we will be able to immerse ourselves in a computer simulation not only of the actual physical world, but of any imagined world. As we begin to move in and out of a computer-generated world, Michael Heim asks, how will the way we perceive our world change?