As the typewriter become popular, it was sometimes referred to it as a “literary piano,” or “the sewing machine of thought.” But the piano and the sewing machine both require a more complex interaction between fingers and machine parts than does the keyboard, which essentially requires you to press whatever button features the letter or symbol you’d like to type. But there is a more complicated sort of keyboard, called a chorded keyboard, that allows for much speedier typing. As interaction designer Bill Buxton has put it, you can think in terms of two extremes: a keyboard with one key for each possible symbol (like the Remington No. 1), or one key that does all symbols (like the Morse key). Today, a standard keyboard is close to one key per symbol, although the shift key (as well as alt, control, command, and so on) complicate the situation. A chorded keyboard takes this principle to the extreme, requiring users to press multiple keys at once. Like playing piano or guitar, typing on a chorded keyboard takes practice. —Slate Magazine.