What Does Digital Mean? - dummies

By Mark L. Chambers

Computers, including MacBooks, are handy machines. They can process information very quickly and never get bored when asked to do the same task millions of times. The problem is that despite their propensity for reliability and speed, they aren’t so hot in the intuition department.

You have to tell them how to do everything (and most of them talk only to application developers and programmers). Computers know only one thing — numbers — although they do know numbers very, very well.

In fact, binary (the language of computers) has only two values — one and zero, which represent on and off, respectively. (Think of a light switch that toggles: The earliest computers were simply banks of switches that filled up an entire room.) To work with a computer in meaningful ways, you have to describe everything to a computer with numbers — or, if you prefer, digits.

By describing audio in numerical digits, you suddenly have something that a computer can work with. Toss a computer as many numbers as you want, and it can handle them. The scientists who figured this out knew that they had a good thing going, so they proceeded to convert anything that they could get their hands on into . . . well, digits. (Sorry about the atrocious pun.)

Anyway, this resulted in some interesting technologies, most of which you’ll surely recognize:

  • Audio CDs: The music is represented as numbers and is stored on a plastic disc.

  • Digital photos: Photographs taken with a digital camera (or scanned from film photographs) can be stored as data.

  • Digital video: Images and sound are stored together on your hard drive or a DVD as one really, really long string of numbers.

  • Digital fingerprints: (No pun intended this time.) Your fingerprint is converted into numerical data, which a computer can use to compare against fingerprint data from other people.

  • Automated telephone operators: When you call a phone operator these days, you often aren’t speaking to a real person. Rather, the computer on the other end of the line converts your voice into digits, which it uses to interpret your words.