# Nature of Electronic Information and How the Electronic Computer Works

FROM THE LECTURE SERIES: THE JOY OF SCIENCE

## Let’s consider the nature of electronic information and the concept behind the great information technology of the time, which is, of course, the electronic computer. A computer is a machine that processes information, and all modern computers rely on these integrated circuits composed of semiconductor materials. These semiconductors help to store information.

### Nature of Electronic Information

Think a bit more about what is meant by “information”. All sorts of sights, all kinds of sounds, photographs, music, words, numbers these all can be represented as information that can be stored and transferred, modified, manipulated in various ways by an electronic computer. This is because all these different kinds of information can be converted into binary digits or bits.

A bit is just one of two states; it’s an object that has either an on or an off, a yes or a no, plus or minus, black and white. Binary codes have been used for a long time. For example, Morse code, the old Morse code that was used by telegraph operators, used pulses that were either long or short. The sequence of long and short pulses are sufficient to communicate any amount of information.

### How to Reduce Ten Digits Into Binary Codes

Indeed, any kind of information can be reduced to bits. For example, let’s think about how to reduce the ten digits from zero to nine into binary. First, you have to think about the places of the binary number. In binary, imagine four decimal places, and the first place represents one. If you have a “1” in that position, you add one to the total; if you have a “0”, it’s just zero.

The second place represents the two columns. If there is a “1” in the two’s column, you add two to your number; if there’s a “0”, it’s zero. The third decimal place is two squared, or four, and the fourth decimal place is two cubed, or eight. So the four places are one, two, four, and eight. In this sort of binary number, then, a one is represented by 0001. A two is represented by 0010, and a four would be represented by 0100.

If you have an odd number, for example, five; well, five is equal to four plus one, so it’d be 0101, and so forth. For those of you listening on audiotape, it will really help to look at your booklet at this point because there’s a list of the binary numbers expressed this way.

This is a transcript from the video series The Joy of ScienceWatch it now, on Wondrium.

### How the Photograph is Reduced to a Bunch of Numbers

Illustrations make a particularly interesting case of how you can digitize information. Imagine your favorite photograph, and how in the world could you reduce that to a bunch of numbers? Well, here’s how they do it. They’re converted to a large number of what are called pixels. Pixels are individual squares of information, each square containing information about color and intensity.

In a typical modern video in North America, you have several hundred rows, each with several hundred pixels. Indeed, TV these days is 525 rows, each with 525 pixels. That gives you a total of 275,000 pixels on each screen. They’re talking about high-density [sic definition] TV or new kinds of high-resolution video images that would have even more information than that, but 275,000 pixels is a lot.

Each of those pixels has to have information on red, how much red is there; how much green is there; and how much blue. The way it’s done, in modern technology, is to have ten bits of information for each of those three colors, or thirty bits of information for every pixel.  If you multiply that out, that’s 30 times 275,000, or eight million bits for every single screen on your TV.

### How the Electronic Computer Works

Computers are designed to store and process numerical information. Typical computers store most of their memory—and that’s typically billions of bits—on magnetic storage devices. On each of these devices, you have small magnetic areas, and the way you store the bit is it’s either north-oriented up or north-oriented down. Zero or one—yes or no.

Today, there are computer disks and diskettes, hard drives, and so forth. They, too, use magnetic storage by having bits oriented north and south. Computations in a computer are carried out in the central processing unit—that’s called the CPU—which typically has one or more integrated circuits made of silicon-based semiconductors.

### Different Materials from Past to Present

Imagine yourself back to the early years of the American republic, two hundred years ago. What materials did people have available then? The artisans of the time would have had just a handful of materials: they had stone; they had wood; they had glass; they had a few types of metals and a few types of alloys to work with. They had some natural fibers.

Today, by contrast, you can find many thousands of different specialized materials. Some of them, like plastics, are so commonplace as to go virtually unnoticed, and yet these are remarkable high-tech materials. Other of these materials, like semiconductors and superconductors, are always hidden away from view in places we never see. We buy a computer, it’s filled with semiconductor materials, but you never see those materials.

Still, other materials, like synthetic diamonds, find use in industry, far away from the consumer. This leads to cheaper cars, much faster eyeglass preparation; quieter, less disruptive repairs of road surfaces, and so forth. New materials, in this context, are usually undramatic. They make very subtle appearances by their physical presence, but they dramatically transform society. Step by step, year by year, people’s lives get better and richer as a result of new materials.

### Common Questions about the Nature of Electronic Information and How the Electronic Computer Works

Q: What’s an electronic computer?

An electronic computer is a machine that processes information. All modern electronic computers today consist of a number of integrated semiconductor circuits. Their function is to process and store information.

Q: What’s meant by “information” in the electronic computer?

In general, information includes all items such as sound, images, music, numbers, and words that can be transmitted and manipulated by the electronic computer. An electronic computer is able to convert and store all information in binary codes and bits.

Q: How does an electronic computer work?

An electronic computer has a central processing unit called a CPU, consisting of several integrated circuits. Integrated circuits are usually made of silicon-based semiconductors. The electronic computer performs calculations in the central processing unit.