VOICE ONE:

This is SCIENCE IN THE NEWS in VOA Special English. I'm Bob Doughty.

VOICE TWO:

And I'm Faith Lapidus. Today we talk about the past, present and future of personal computers.

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VOICE ONE:

You could say the first personal computers were the simple counting devices of ancient times. But maybe we are going back too far.

Some people would say the first real counting machines were the inventions of Blaise Pascal in the middle of the 1600s. Pascal was a French scientist and inventor who designed a machine with wheels and cuts. These worked together to add or take away numbers.

A few years later, a German scientist improved on Pascal's work and created a system that permitted multiplication and division.

VOICE TWO:

In the same period, an Englishman named George Boole developed a math system based on zero and one. Boolean logic was important to the development of the computers of today.

But we still have some more historical ground to cover.

In eighteen ninety, census workers counted the United States population with help from a system designed by Herman Hollerith. That system, designed two years earlier, used two machines. One machine put holes into paper to mark information. The other machine quickly read the holes and produced a final count.

VOICE ONE:

Herman Hollerith went on to establish a company called Tabulating Business Machines. In 1911 he sold the company -- and 13 years later it became International Business Machines. The company had already been operating under the IBM name in Canada.

So now we jump from 1924 to 1981 -- August 20th, 1981, to be exact. That was the day the company announced a new product called the IBM Personal Computer. It was not the first personal computer ever invented, but its success helped build a new market.

So now we are up to the age of the modern P.C. But we have left out some steps along the way.

VOICE TWO:

In 1930, the analog computer used gears and shafts to solve differential equations. Complex mathematics became easier.

Later, IBM's Mark One computer performed operations using a system of electromechanical switches.

Then in 1946 came the Electronic Numerical Integrator and Computer -- ENIAC. It used a system of vacuum tubes.

ENIAC was huge. It took up almost 170 square meters in a building at the University of Pennsylvania. ENIAC was unlike anything before. Its digital processing was lightning fast, at least compared to older computers.

Analog computers used moving parts. Digital devices process information electronically in the form of numbers. The difference was like night and day.

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VOICE ONE:

Until the 1970s, computers were far too big and costly for the average person. There were mostly mainframe computers in government agencies, research centers and big companies.

But people found ways to shrink computers, and to increase the power and speed. Transistors replaced vacuum tubes. Later, integrated circuits combined many transistors on a single small chip.

The Apple Computer Company in California started selling personal computers in the late seventies. But the IBM Personal Computer is credited with producing widespread interest in home computers.

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