powell@decwrl.UUCP (11/03/83)
From: Mike Powell <powell> The following are excerpts from "But How Do Computers Do All That?" in the Ladies' Home Journal, September 1983. If the kids can understand them, so can you. Here, Dr. David Gries, chairman of computer sciences at Cornell University, answers the questions we all have. ... LHJ: What's the difference between a hard disc and a floppy disc? DR. GRIES: Hard discs are very expensive and can be used only once. Once the information is stored, you can't change it, so hard discs are good only for industrial uses such as operating instructions for machinery or huge permanent files. Floppy discs are affordable, portable, and can be used either for permanent files or over and over again. ... LHJ: So the computer is only as knowledgeable as the people who use it? DR. GRIES: Exactly. The computers we have aren't anything like the human brain. That's why they have trouble doing things that require real thinking, such as playing chess. I play chess with my computer, but when I look at the game board, I perceive the whole pattern and go through some rapid thought processes I'm not even aware of as I rely on past experience and knowledge in planning my strategy. But the computer has to look at each square separately, register what pieces are where, file through a pre-programmed list of possible moves, and pick one. It's not very efficient or brilliant, and, of course, if it hasn't been programmed with enough possible moves, it can't do anything about that. It can't think up anything.