Blaise Pascal invented the second mechanical calculator, called alternatively the Pascalina or the Arithmetique, in 1645, the first being that of Wilhelm Schickard in 1623.
Pascal began work on his calculator in 1642, when he was only 19 years old. He had been assisting his father, who worked as a tax commissioner, and sought to produce a device which could reduce some of his workload. Pascal received a Royal Privilege in 1649 that granted him exclusive rights to make and sell calculating machines in France. By 1652 Pascal claimed to have produced some fifty prototypes and sold just over a dozen machines, but the cost and complexity of the Pascaline—combined with the fact that it could only add and subtract, and the latter with difficulty—was a barrier to further sales, and production ceased in that year. By that time Pascal had moved on to other pursuits, initially the study of atmospheric pressure, and later philosophy.
Pascaline made for French currency. The least significant denominations, sols and deniers, are on the right.
Pascalines came in both decimal and non-decimal varieties, both of which exist in museums today. The contemporary French currency system was similar to the Imperial pounds ("livres"), shillings ("sols") and pence ("deniers") in use in Britain until the 1970s.
In 1799 France changed to a metric system, by which time Pascal's basic design had inspired other craftsmen, although with a similar lack of commercial success. Child prodigy Gottfried Wilhelm Leibniz devised a competing design, the Stepped Reckoner, in 1672 which could perform addition, subtraction, multiplication and division; Leibniz struggled for forty years to perfect his design and produce sufficiently reliable machines. Calculating machines did not become commercially viable until the early 19th century, when Charles Xavier Thomas de Colmar's Arithmometer, itself using the key break through of Leibniz's design, was commercially successful.
The initial prototype of the Pascaline had only a few dials, whilst later production variants had eight dials, the latter being able to deal with numbers up to 9,999,999.
View through back of calculator above showing wheels.
The calculator had spoked metal wheel dials, with the digit 0 through 9 displayed around the circumference of each wheel. To input a digit, the user placed a stylus in the corresponding space between the spokes, and turned the dial until a metal stop at the bottom was reached, similar to the way a rotary telephone dial is used. This would display the number in the boxes at the top of the calculator. Then, one would simply redial the second number to be added, causing the sum of both numbers to appear in boxes at the top. Since the gears of the calculator only rotated in one direction, negative numbers could not be directly summed. To subtract one number from another, the method of nines' complements was used. To help the user, when a number was entered its nines' complement appeared in a box above the box containing the original value entered. y mi mejor amiga nerea lauren y daniela
jueves, 26 de febrero de 2009
First Computers: Pascal's Calculator
Blaise Pascal invented the second mechanical calculator, called alternatively the Pascalina or the Arithmetique, in 1645, the first being that of Wilhelm Schickard in 1623.
Pascal began work on his calculator in 1642, when he was only 19 years old. He had been assisting his father, who worked as a tax commissioner, and sought to produce a device which could reduce some of his workload. Pascal received a Royal Privilege in 1649 that granted him exclusive rights to make and sell calculating machines in France. By 1652 Pascal claimed to have produced some fifty prototypes and sold just over a dozen machines, but the cost and complexity of the Pascaline—combined with the fact that it could only add and subtract, and the latter with difficulty—was a barrier to further sales, and production ceased in that year. By that time Pascal had moved on to other pursuits, initially the study of atmospheric pressure, and later philosophy.
Pascaline made for French currency. The least significant denominations, sols and deniers, are on the right.
Pascalines came in both decimal and non-decimal varieties, both of which exist in museums today. The contemporary French currency system was similar to the Imperial pounds ("livres"), shillings ("sols") and pence ("deniers") in use in Britain until the 1970s.
In 1799 France changed to a metric system, by which time Pascal's basic design had inspired other craftsmen, although with a similar lack of commercial success. Child prodigy Gottfried Wilhelm Leibniz devised a competing design, the Stepped Reckoner, in 1672 which could perform addition, subtraction, multiplication and division; Leibniz struggled for forty years to perfect his design and produce sufficiently reliable machines. Calculating machines did not become commercially viable until the early 19th century, when Charles Xavier Thomas de Colmar's Arithmometer, itself using the key break through of Leibniz's design, was commercially successful.
The initial prototype of the Pascaline had only a few dials, whilst later production variants had eight dials, the latter being able to deal with numbers up to 9,999,999.
View through back of calculator above showing wheels.
The calculator had spoked metal wheel dials, with the digit 0 through 9 displayed around the circumference of each wheel. To input a digit, the user placed a stylus in the corresponding space between the spokes, and turned the dial until a metal stop at the bottom was reached, similar to the way a rotary telephone dial is used. This would display the number in the boxes at the top of the calculator. Then, one would simply redial the second number to be added, causing the sum of both numbers to appear in boxes at the top. Since the gears of the calculator only rotated in one direction, negative numbers could not be directly summed. To subtract one number from another, the method of nines' complements was used. To help the user, when a number was entered its nines' complement appeared in a box above the box containing the original value entered.
Pascal began work on his calculator in 1642, when he was only 19 years old. He had been assisting his father, who worked as a tax commissioner, and sought to produce a device which could reduce some of his workload. Pascal received a Royal Privilege in 1649 that granted him exclusive rights to make and sell calculating machines in France. By 1652 Pascal claimed to have produced some fifty prototypes and sold just over a dozen machines, but the cost and complexity of the Pascaline—combined with the fact that it could only add and subtract, and the latter with difficulty—was a barrier to further sales, and production ceased in that year. By that time Pascal had moved on to other pursuits, initially the study of atmospheric pressure, and later philosophy.
Pascaline made for French currency. The least significant denominations, sols and deniers, are on the right.
Pascalines came in both decimal and non-decimal varieties, both of which exist in museums today. The contemporary French currency system was similar to the Imperial pounds ("livres"), shillings ("sols") and pence ("deniers") in use in Britain until the 1970s.
In 1799 France changed to a metric system, by which time Pascal's basic design had inspired other craftsmen, although with a similar lack of commercial success. Child prodigy Gottfried Wilhelm Leibniz devised a competing design, the Stepped Reckoner, in 1672 which could perform addition, subtraction, multiplication and division; Leibniz struggled for forty years to perfect his design and produce sufficiently reliable machines. Calculating machines did not become commercially viable until the early 19th century, when Charles Xavier Thomas de Colmar's Arithmometer, itself using the key break through of Leibniz's design, was commercially successful.
The initial prototype of the Pascaline had only a few dials, whilst later production variants had eight dials, the latter being able to deal with numbers up to 9,999,999.
View through back of calculator above showing wheels.
The calculator had spoked metal wheel dials, with the digit 0 through 9 displayed around the circumference of each wheel. To input a digit, the user placed a stylus in the corresponding space between the spokes, and turned the dial until a metal stop at the bottom was reached, similar to the way a rotary telephone dial is used. This would display the number in the boxes at the top of the calculator. Then, one would simply redial the second number to be added, causing the sum of both numbers to appear in boxes at the top. Since the gears of the calculator only rotated in one direction, negative numbers could not be directly summed. To subtract one number from another, the method of nines' complements was used. To help the user, when a number was entered its nines' complement appeared in a box above the box containing the original value entered.
First Computers: Abacus
An abacus, also called a counting frame, is a calculating tool used primarily in parts of Asia for performing arithmetic processes. Today, abacuses are often constructed as a bamboo frame with beads sliding on wires, but originally they were beans or stones moved in grooves in sand or on tablets of wood, stone, or metal. The abacus was in use centuries before the adoption of the written modern numeral system and is still widely used by merchants, traders and clerks in Asia, Africa, and elsewhere.
The user of an abacus is called an abacist; he or she slides the beads of the abacus by hand.
The user of an abacus is called an abacist; he or she slides the beads of the abacus by hand.
Computer Generations: 5th Generation - Artificial Intelligence
Fifth generation computing devices, based on artificial intelligence, are still in development, though there are some applications, such as voice recognition, that are being used today. The use of parallel processing and superconductors is helping to make artificial intelligence a reality. Quantum computation and molecular and nanotechnology will radically change the face of computers in years to come. The goal of fifth-generation computing is to develop devices that respond to natural language input and are capable of learning and self-organization.
Computer Generations: 4th Generation - Microprocessors
The microprocessor brought the fourth generation of computers, as thousands of integrated circuits were built onto a single silicon chip. What in the first generation filled an entire room could now fit in the palm of the hand. The Intel 4004 chip, developed in 1971, located all the components of the computer - from the central processing unit and memory to input/output controls - on a single chip.
In 1981 IBM introduced its first computer for the home user, and in 1984 Apple introduced the Macintosh. Microprocessors also moved out of the realm of desktop computers and into many areas of life as more and more everyday products began to use microprocessors.
As these small computers became more powerful, they could be linked together to form networks, which eventually led to the development of the Internet. Fourth generation computers also saw the development of GUIs, the mouse and handheld devices.
In 1981 IBM introduced its first computer for the home user, and in 1984 Apple introduced the Macintosh. Microprocessors also moved out of the realm of desktop computers and into many areas of life as more and more everyday products began to use microprocessors.
As these small computers became more powerful, they could be linked together to form networks, which eventually led to the development of the Internet. Fourth generation computers also saw the development of GUIs, the mouse and handheld devices.
Computer Generations: 3rd Generation - Integrated Circuits
The development of the integrated circuit was the hallmark of the third generation of computers. Transistors were miniaturized and placed on silicon chips, called semiconductors, which drastically increased the speed and efficiency of computers.
Instead of punched cards and printouts, users interacted with third generation computers through keyboards and monitors and interfaced with an operating system, which allowed the device to run many different applications at one time with a central program that monitored the memory. Computers for the first time became accessible to a mass audience because they were smaller and cheaper than their predecessors.
Instead of punched cards and printouts, users interacted with third generation computers through keyboards and monitors and interfaced with an operating system, which allowed the device to run many different applications at one time with a central program that monitored the memory. Computers for the first time became accessible to a mass audience because they were smaller and cheaper than their predecessors.
Computer Generations: 2nd Generation - Transistors
Transistors replaced vacuum tubes and ushered in the second generation of computers. The transistor was invented in 1947 but did not see widespread use in computers until the late 50s. The transistor was far superior to the vacuum tube, allowing computers to become smaller, faster, cheaper, more energy-efficient and more reliable than their first-generation predecessors. Though the transistor still generated a great deal of heat that subjected the computer to damage, it was a vast improvement over the vacuum tube. Second-generation computers still relied on punched cards for input and printouts for output.
Second-generation computers moved from cryptic binary machine language to symbolic, or assembly, languages, which allowed programmers to specify instructions in words. High-level programming languages were also being developed at this time, such as early versions of COBOL and FORTRAN. These were also the first computers that stored their instructions in their memory, which moved from a magnetic drum to magnetic core technology.
The first computers of this generation were developed for the atomic energy industry.
Second-generation computers moved from cryptic binary machine language to symbolic, or assembly, languages, which allowed programmers to specify instructions in words. High-level programming languages were also being developed at this time, such as early versions of COBOL and FORTRAN. These were also the first computers that stored their instructions in their memory, which moved from a magnetic drum to magnetic core technology.
The first computers of this generation were developed for the atomic energy industry.
Computer Generations: 1st Generation - Vacuum Tubes
+he first computers used vacuum tubes for circuitry and magnetic drums for memory, and were often enormous, taking up entire rooms. They were very expensive to operate and in addition to using a great deal of electricity, generated a lot of heat, which was often the cause of malfunctions.
First generation computers relied on machine language, the lowest-level programming language understood by computers, to perform operations, and they could only solve one problem at a time. Input was based on punched cards and paper tape, and output was displayed on printouts.
The UNIVAC and ENIAC computers are examples of first-generation computing devices. The UNIVAC was the first commercial computer delivered to a business client, the U.S. Census Bureau in 1951.
First generation computers relied on machine language, the lowest-level programming language understood by computers, to perform operations, and they could only solve one problem at a time. Input was based on punched cards and paper tape, and output was displayed on printouts.
The UNIVAC and ENIAC computers are examples of first-generation computing devices. The UNIVAC was the first commercial computer delivered to a business client, the U.S. Census Bureau in 1951.
Suscribirse a:
Entradas (Atom)