“What made word-processing devices much more than just souped-up typewriters was not only that they gave you the ability to edit at the same time that you wrote, or that they eliminated or seriously curtailed the effort of correcting from typewritten pages. Seeing text revealed on a screen, even in the technologically costive form offered by the earliest word processors, provided an unprecedented opportunity to picture the manuscript as a whole and with an immediacy that typewriting didn’t permit.”