You can't go anywhere these days without bumping into the word "digital." Ads are rampant for digital music players, digital picture makers, and digital watches. Clocks, radios, calendars, and other novelties are being sold as digital by simple-minded (r wily) copywriters.

We have some news for them. Frank wears a watch whose face has two hands that point at the 12 digits, but inside it's technologically digital as all get-out. And most cheap clocks that display time on plastic blocks numbered 0 through 9 are not electronically digital at all.Digital, used electronically, refers to information expressed in only two precise digits, zero and one. Zero is used to indicate that there's nothing present or nothing happening. (o far, pretty much standard English.) But one now means (igitally speaking) that something is present or something is happening.

Here's where the reasoning gets a little tricky. Because when "one" is used to show that something is present, what's there is precisely one unit of whatever it is. If one is used to show that something is happening, it shows only one event of that something.

Let's examine an imaginary light switch, digitally speaking. If it's off, we write zero. If it's on, we write one. In the fictional "digital house" of our analogy, the light switches can't have dimmers. They can't be partially on.

Working only with two digits, 0 and 1, can be a real handicap. Even counting a handful of apples results in very long numbers. A couple of apples aren't 2 any more since 2 doesn't exist; they're 10. A half dozen apples, in digital counting, is 110. A hundred apples is 1100100.

The opposite of digital is analog. Remember the old game in which the leader whispers a complicated sentence to the first player, who whispers it to the second player and so on? By the time the whisper reaches the leader again, the message is usually garbled. That's because it's based on analog information.

Let's change the rules so that, instead of whispering, each player has a flashlight and a card showing the Morse Code. Relaying the message using DOT DASH for `A' and DOT DOT DOT DASH for `V' is awfully slow. But it's completely accurate. And it's digital, the DOT being akin to zero and the DASH akin to the number one.

When scientists started messing with computers, they tried to use an analog system just like the whisper. Simple? Ah, but in a long wire, voltage drops. At the other end the 24 volts might come out as 22, and there goes accuracy. Computers would have gone the way of Edsels, if somebody hadn't remembered the digital system.

Using digital science, it won't matter how long the wire is. Let's imagine that, on the dot of every second, you either jab once on Earth's doorbell or jab not at all. Your friend, waiting for your message at the other end of the globe, expects a 1 or 0 every second on the dot. The accuracy of message sending between you will reach very close to 100 percent.

The processing chip inside an average personal computer is no bigger than a nickel. But if the circuits etched into it were stretched out, they'd encircle the globe. If we were stuck with analog technology, by the time a 24-volt input reached one stop, it'd be 20 volts. By the time it reached the next stop it'd be 18 volts. The IRS computers would never be able to compute your correct taxes.

A computer computes at nearly the speed of light. The digital system is slow compared to analog, but at those computing speeds it can compute the distance from Moscow to Mazomanie in less time than it takes to say the two words.

If you have a digital watch, there are tiny chips inside which compute the time and date. If you have a digital radio, there are tiny chips inside which compute the frequency of your favorite FM station. If you have a digital thermostat, the temperature is digitally computed inside.

You'd still be yelling into a phone to make crackly long distance phone calls, if Mother Bell and the boys hadn't figured out how to turn your voice into digital signals in Moscow (daho) and convert the digits back into analogs in Mazomanie (isconsin).

And we all used to think that a zero was worth nothing at all!

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