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not know how human beings die artithmetic before the time of the great civilizations.Anything more than simple addition would have been very difficult,so it is fortunate that simple societies have little need for arithmetic.
But advanced cultures have always needed arithmetic.Goods must be bought and sold and measured.Taxes must be computed and collected.Soldiers have to be paid.Yet even in the advanced civilizations of ancient times-Egypt,Greece,Rome,China,the near East-calculating was a formidable task.Imagine,for instance,the problems of a Roman accountant faced with columns of Roman numerals to add up.Subtraction would have been no easier.Multiplication and division must have been nearly impossible.
To cope with these difficulties,each of these ancient peoples invented a simple calculating device based on the decimal system.The physical form of the device varied,but usually it was a shallow box containing pebbles or other movable counters.The best version was invented by the babylonians;it was used today in many parts of the world.It is the abacus.The "heaved-and-earth"abacus,an improved form developed in late Roman times,is still common in Russia and China.Therefor,the credit for inventing the first digital calculator goes to the Babylonians some four thousand years ago.(The defference between the digital calculator and the analog calculator is obvious.Adigital calculator represents numbers as counting symbols,whtile an analog calculator is obvious.Adigital caculator represents numbers as counting symbol,while an analog calculator represents numbers as lengths,electrical voltages or other physical quantities.An abacus gives the precise digital answers,while an analog device gives only approximate answers.)
After the abacus,the nest great advance toward the modern computer was made in the seventeenth century.In the nest three centuries since then
,pioneers had worked singly or in groups to make the computer ever more sophisticate,useful,powerful,and versatile.It was Pascal who at the age of niniteen made the first advance in computing since the invertion of abacus nearly four thousand years before his time.Pascal's machine was an adding and subtraction machine only.The machine was named Pascalin.Pascaline was digital;that is ,like the abacus,it dealt with whole numbers and produced precise results.In the years that followed Pascal's invention,many attempts were made to invent a machine that would perform all four arithmetic functions but unsuccesful.Finally,an English mathematician named Charles Babbage conceived the idea of a machine which could carry out complicated calculations and could also be completely automatic.As a mathematician,Babbage had to deal with long calculations and was getting bored with them,so he designed his Analytical Engine.The machine was to read data and programs from cards.however,Babbage's Analytical Engine proved too comples for him to build.His idea was ahead of the technology of his time.Later,Ada lovelace improved Babbage's Analytical Engine.Not long afterwards,William Burroughs made Burroughs Adding and Listing Machine;Herman Hollerith developed the first electromechanical punched-card tabulator.Since technologies are interwoven and independent,the evolution of the computer was slow and difficult until the arrival of electonic age.The computer as we see it now is a product of that age.Its further evolution waits for progress in other technologies,or perhaps a nes technology altogether.
not know how human beings die artithmetic before the time of the great civilizations.Anything more than simple addition would have been very difficult,so it is fortunate that simple societies have little need for arithmetic.
But advanced cultures have always needed arithmetic.Goods must be bought and sold and measured.Taxes must be computed and collected.Soldiers have to be paid.Yet even in the advanced civilizations of ancient times-Egypt,Greece,Rome,China,the near East-calculating was a formidable task.Imagine,for instance,the problems of a Roman accountant faced with columns of Roman numerals to add up.Subtraction would have been no easier.Multiplication and division must have been nearly impossible.
To cope with these difficulties,each of these ancient peoples invented a simple calculating device based on the decimal system.The physical form of the device varied,but usually it was a shallow box containing pebbles or other movable counters.The best version was invented by the babylonians;it was used today in many parts of the world.It is the abacus.The "heaved-and-earth"abacus,an improved form developed in late Roman times,is still common in Russia and China.Therefor,the credit for inventing the first digital calculator goes to the Babylonians some four thousand years ago.(The defference between the digital calculator and the analog calculator is obvious.Adigital calculator represents numbers as counting symbols,whtile an analog calculator is obvious.Adigital caculator represents numbers as counting symbol,while an analog calculator represents numbers as lengths,electrical voltages or other physical quantities.An abacus gives the precise digital answers,while an analog device gives only approximate answers.)
After the abacus,the nest great advance toward the modern computer was made in the seventeenth century.In the nest three centuries since then
,pioneers had worked singly or in groups to make the computer ever more sophisticate,useful,powerful,and versatile.It was Pascal who at the age of niniteen made the first advance in computing since the invertion of abacus nearly four thousand years before his time.Pascal's machine was an adding and subtraction machine only.The machine was named Pascalin.Pascaline was digital;that is ,like the abacus,it dealt with whole numbers and produced precise results.In the years that followed Pascal's invention,many attempts were made to invent a machine that would perform all four arithmetic functions but unsuccesful.Finally,an English mathematician named Charles Babbage conceived the idea of a machine which could carry out complicated calculations and could also be completely automatic.As a mathematician,Babbage had to deal with long calculations and was getting bored with them,so he designed his Analytical Engine.The machine was to read data and programs from cards.however,Babbage's Analytical Engine proved too comples for him to build.His idea was ahead of the technology of his time.Later,Ada lovelace improved Babbage's Analytical Engine.Not long afterwards,William Burroughs made Burroughs Adding and Listing Machine;Herman Hollerith developed the first electromechanical punched-card tabulator.Since technologies are interwoven and independent,the evolution of the computer was slow and difficult until the arrival of electonic age.The computer as we see it now is a product of that age.Its further evolution waits for progress in other technologies,or perhaps a nes technology altogether.
