Computing hardware evolved from
machines that needed separate manual
action to perform each arithmetic
operation, to punched card machines,
and then to stored-program computers.
The history of stored-program
computers relates first to computer
architecture, that is, the organization of
the units to perform input and output,
to store data and to operate as an
integrated mechanism.
Before the development of the general-
purpose computer, most calculations
were done by humans. Mechanical tools
to help humans with digital calculations
were then called"calculating machines",
by proprietary names, or even as they
are now, calculators. It was those
humans who used the machines who
were then called computers. Aside from
written numerals, the first aids to
computation were purely mechanical
devices which required the operator to
set up the initial values of an
elementary arithmetic operation, then
manipulate the device to obtain the
result. A sophisticated (and
comparatively recent) example is the
slide rule in which numbers are
represented as lengths on a logarithmic
scale and computation is performed by
setting a cursor and aligning sliding
scales, thus adding those lengths.
Numbers could be represented in a
continuous"analog"form, for instance
a voltage or some other physical
property was set to be proportional to
the number. Analog computers, like
those designed and built by Vannevar
Bush before World War II were of this
type. Numbers could be represented in
the form of digits, automatically
manipulated by a mechanical
mechanism. Although this last approach
required more complex mechanisms in
many cases, it made for greater
precision of results.
The invention of electronic amplifiers
made calculating machines much faster
than their mechanical or
electromechanic -al predecessors.
Vacuum tube (thermionic valve)
amplifiers gave way to solid state
transistors, and then rapidly to
integrated circuits which continue to
improve, placing millions of electrical
switches (typically transistors) on a
single elaborately manufactured piece
of semi-conductor the size of a
fingernail. By defeating the tyranny of
numbers, integrated circuits made high-
speed and low-cost digital computers a
widespread commodity. There is an
ongoing effort to make computer
hardware faster, cheaper, and capable
of storing more data.
Computing hardware has become a
platform for uses other than mere
computation, such as process
automation, electronic communications,
equipment control, entertainment,
education, etc. Each field in turn has
imposed its own requirements on the
hardware, which has evolved in
response to those requirements, such
as the role of the touch screen to create
a more intuitive and natural user
interface.
As all computers rely on digital storage,
and tend to be limited by the size and
speed of memory, the history of
computer data storage is tied to the
development of computers.
Earliest true hardware
Devices have been used to aid
computation for thousands of years,
mostly using one-to-one
correspondence with our fingers. The
earliest counting device was probably
form of tally stick. Later record keeping
aids throughout the Fertile Crescent
included calculi (clay spheres, cones,
etc.) which represented counts of items,
probably livestock or grains. The use of counting
rods is one example.
The abacus was early used for
arithmetic tasks. What we now call the
Roman abacus was used in Babylonia
as early as 2400 BC. Since then, many
other forms of reckoning boards or
tables have been invented. In a
medieval European counting house, a
checkered cloth would be placed on a
table, and markers moved around on it
according to certain rules, as an aid to
calculating sums of money.
Several analog computers were
constructed in ancient and medieval
times to perform astronomical
calculations. These include the
Antikythera mechanism and the
astrolabe from ancient Greece (c. 150–
100 BC), which are generally regarded
as the earliest known mechanical
analog computers.Hero of Alexandria
(c. 10–70 AD) made many complex
mechanical devices including automata
and a programmable cart. Other
early versions of mechanical devices
used to perform one or another type of
calculations include the planisphere and
other mechanical computing devices
invented by Abū Rayhān al-Bīrūnī (c. AD
1000); the equatorium and universal
latitude-indepe -ndent astrolabe by Abū
Ishāq Ibrāhīm al-Zarqālī (c. AD 1015);
the astronomical analog computers of
other medieval Muslim astronomers
and engineers; and the astronomical
clock tower of Su Song (c. AD 1090)
during the Song Dynasty.Scottis -h mathematician and physicist
John Napier noted multiplication and
division of numbers could be
performed by addition and subtraction,
respectively, of logarithms of those
numbers. While producing the first
logarithmic tables Napier needed to
perform many multiplications -, and it
was at this point that he designed
Napier's bones, an abacus-like device
used for multiplication and division.
Since real numbers can be represented
as distances or intervals on a line, the
slide rule was invented in the 1620s to
allow multiplication and division
operations to be carried out
significantly faster than was previously
possible.Slide rules were used by
generations of engineers and other
mathematically involved professional
workers, until the invention of the
pocket calculator.
Wilhelm Schickard, a German polymath,
designed a calculating clock in 1623. It
made use of a single-tooth gear that
was not an adequate solution for a
general carry mechanism. A fire destroyed the machine during its
construction in 1624 and Schickard
abandoned the project. Two sketches
of it were discovered in 1957, too late
to have any impact on the development
of mechanical calculators. In 1642, while still a teenager, Blaise
Pascal started some pioneering work
on calculating machines and after three
years of effort and 50 prototypes
he invented the mechanical
calculator. He built twenty of these machines (called Pascal's
Calculator or Pascaline) in the following
ten years. Nine Pascalines have
survived, most of which are on display
in European museums.Gottfried Wilhelm
von Leibniz invented the Stepped Reckoner and his famous
cylinders around 1672 while adding
direct multiplication and division to the
Pascaline. Leibniz once said "It is
unworthy of excellent men to lose
hours like slaves in the labour of calculation which could safely be
relegated to anyone else if machines
were used."
Around 1820, Charles Xavier Thomas de
Colmar created the first successful,
mass-produced mechanical calculator, the Thomas Arithmometer, that could
add, subtract, multiply, and divide.
It was mainly based on Leibniz' work.
Mechanical calculators, like the base-ten
addiator, the comptometer, the Monroe,
the Curta and the Addo-X remained in use until the 1970s. Leibniz also
described the binary numeral
system, a central ingredient of all
modern computers. However, up to the
1940s, many subsequent designs
(including Charles Babbage's machines of the 1822 and even ENIAC of 1945)
were based on the decimal system;
ENIAC's ring counters emulated the
operation of the digit wheels of a
mechanical adding machine.
In Japan, Ryoichi Yazu patented a mechanical calculator called the Yazu
Arithmometer in 1903. It consisted of a
single cylinder and 22 gears, and
employed the mixed base-2 and base-5
number system familiar to users to the
soroban (Japanese abacus). Carry and end of calculation were determined
automatically. More than 200 units
were sold, mainly to government
agencies such as the Ministry of War
and agricultural experiment
stations.
This article is submitted by SNEHA SHARE..You Can Also SUBMIT a article here ..VISIT THIS LINK >>Post A ARTICLE
machines that needed separate manual
action to perform each arithmetic
operation, to punched card machines,
and then to stored-program computers.
The history of stored-program
computers relates first to computer
architecture, that is, the organization of
the units to perform input and output,
to store data and to operate as an
integrated mechanism.
Before the development of the general-
purpose computer, most calculations
were done by humans. Mechanical tools
to help humans with digital calculations
were then called"calculating machines",
by proprietary names, or even as they
are now, calculators. It was those
humans who used the machines who
were then called computers. Aside from
written numerals, the first aids to
computation were purely mechanical
devices which required the operator to
set up the initial values of an
elementary arithmetic operation, then
manipulate the device to obtain the
result. A sophisticated (and
comparatively recent) example is the
slide rule in which numbers are
represented as lengths on a logarithmic
scale and computation is performed by
setting a cursor and aligning sliding
scales, thus adding those lengths.
Numbers could be represented in a
continuous"analog"form, for instance
a voltage or some other physical
property was set to be proportional to
the number. Analog computers, like
those designed and built by Vannevar
Bush before World War II were of this
type. Numbers could be represented in
the form of digits, automatically
manipulated by a mechanical
mechanism. Although this last approach
required more complex mechanisms in
many cases, it made for greater
precision of results.
The invention of electronic amplifiers
made calculating machines much faster
than their mechanical or
electromechanic -al predecessors.
Vacuum tube (thermionic valve)
amplifiers gave way to solid state
transistors, and then rapidly to
integrated circuits which continue to
improve, placing millions of electrical
switches (typically transistors) on a
single elaborately manufactured piece
of semi-conductor the size of a
fingernail. By defeating the tyranny of
numbers, integrated circuits made high-
speed and low-cost digital computers a
widespread commodity. There is an
ongoing effort to make computer
hardware faster, cheaper, and capable
of storing more data.
Computing hardware has become a
platform for uses other than mere
computation, such as process
automation, electronic communications,
equipment control, entertainment,
education, etc. Each field in turn has
imposed its own requirements on the
hardware, which has evolved in
response to those requirements, such
as the role of the touch screen to create
a more intuitive and natural user
interface.
As all computers rely on digital storage,
and tend to be limited by the size and
speed of memory, the history of
computer data storage is tied to the
development of computers.
Earliest true hardware
Devices have been used to aid
computation for thousands of years,
mostly using one-to-one
correspondence with our fingers. The
earliest counting device was probably
form of tally stick. Later record keeping
aids throughout the Fertile Crescent
included calculi (clay spheres, cones,
etc.) which represented counts of items,
probably livestock or grains. The use of counting
rods is one example.
The abacus was early used for
arithmetic tasks. What we now call the
Roman abacus was used in Babylonia
as early as 2400 BC. Since then, many
other forms of reckoning boards or
tables have been invented. In a
medieval European counting house, a
checkered cloth would be placed on a
table, and markers moved around on it
according to certain rules, as an aid to
calculating sums of money.
Several analog computers were
constructed in ancient and medieval
times to perform astronomical
calculations. These include the
Antikythera mechanism and the
astrolabe from ancient Greece (c. 150–
100 BC), which are generally regarded
as the earliest known mechanical
analog computers.Hero of Alexandria
(c. 10–70 AD) made many complex
mechanical devices including automata
and a programmable cart. Other
early versions of mechanical devices
used to perform one or another type of
calculations include the planisphere and
other mechanical computing devices
invented by Abū Rayhān al-Bīrūnī (c. AD
1000); the equatorium and universal
latitude-indepe -ndent astrolabe by Abū
Ishāq Ibrāhīm al-Zarqālī (c. AD 1015);
the astronomical analog computers of
other medieval Muslim astronomers
and engineers; and the astronomical
clock tower of Su Song (c. AD 1090)
during the Song Dynasty.Scottis -h mathematician and physicist
John Napier noted multiplication and
division of numbers could be
performed by addition and subtraction,
respectively, of logarithms of those
numbers. While producing the first
logarithmic tables Napier needed to
perform many multiplications -, and it
was at this point that he designed
Napier's bones, an abacus-like device
used for multiplication and division.
Since real numbers can be represented
as distances or intervals on a line, the
slide rule was invented in the 1620s to
allow multiplication and division
operations to be carried out
significantly faster than was previously
possible.Slide rules were used by
generations of engineers and other
mathematically involved professional
workers, until the invention of the
pocket calculator.
Wilhelm Schickard, a German polymath,
designed a calculating clock in 1623. It
made use of a single-tooth gear that
was not an adequate solution for a
general carry mechanism. A fire destroyed the machine during its
construction in 1624 and Schickard
abandoned the project. Two sketches
of it were discovered in 1957, too late
to have any impact on the development
of mechanical calculators. In 1642, while still a teenager, Blaise
Pascal started some pioneering work
on calculating machines and after three
years of effort and 50 prototypes
he invented the mechanical
calculator. He built twenty of these machines (called Pascal's
Calculator or Pascaline) in the following
ten years. Nine Pascalines have
survived, most of which are on display
in European museums.Gottfried Wilhelm
von Leibniz invented the Stepped Reckoner and his famous
cylinders around 1672 while adding
direct multiplication and division to the
Pascaline. Leibniz once said "It is
unworthy of excellent men to lose
hours like slaves in the labour of calculation which could safely be
relegated to anyone else if machines
were used."
Around 1820, Charles Xavier Thomas de
Colmar created the first successful,
mass-produced mechanical calculator, the Thomas Arithmometer, that could
add, subtract, multiply, and divide.
It was mainly based on Leibniz' work.
Mechanical calculators, like the base-ten
addiator, the comptometer, the Monroe,
the Curta and the Addo-X remained in use until the 1970s. Leibniz also
described the binary numeral
system, a central ingredient of all
modern computers. However, up to the
1940s, many subsequent designs
(including Charles Babbage's machines of the 1822 and even ENIAC of 1945)
were based on the decimal system;
ENIAC's ring counters emulated the
operation of the digit wheels of a
mechanical adding machine.
In Japan, Ryoichi Yazu patented a mechanical calculator called the Yazu
Arithmometer in 1903. It consisted of a
single cylinder and 22 gears, and
employed the mixed base-2 and base-5
number system familiar to users to the
soroban (Japanese abacus). Carry and end of calculation were determined
automatically. More than 200 units
were sold, mainly to government
agencies such as the Ministry of War
and agricultural experiment
stations.
This article is submitted by SNEHA SHARE..You Can Also SUBMIT a article here ..VISIT THIS LINK >>
0 comments:
Post a Comment