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 | | I need some articles about computer viruses? (Answers: 4) |  Security |  I need some articles about viruses, for example, how add shell to computer viruses, where I can find some articles. Don't worry about that, I just want some articles to write my essay. Thanks a lot. |  here's article about what is computer virus and what can it dohttp://www.2-spyware.com/viruses-removal |
| | | intoduction articles for computer? (Answers: 1) | | Internet | | introduction topics on computer | A computer is a machine for manipulating data according to a list of instructions.Computers take numerous physical forms. Early electronic computers were the size of
a large room, consuming as much power as several hundred modern personal computers. [1] Today, computers can be made small enough to fit into a wrist watch and be
powered from a watch battery. Society has come to recognize personal computers and their portable equivalent, the laptop computer, as icons of the information age;
they are what most people think of as "a computer". However, the most common form of computer in use today is by far the embedded computer. Embedded computers are
small, simple devices that are often used to control other devices—for example, they may be found in machines ranging from fighter aircraft to industrial robots,
digital cameras, and even children's toys.A computer in a wristwatch.A computer in a wristwatch.The ability to store and execute programs makes computers extremely
versatile and distinguishes them from calculators. The Church–Turing thesis is a mathematical statement of this versatility: Any computer with a certain minimum
capability is, in principle, capable of performing the same tasks that any other computer can perform. Therefore, computers with capability and complexity ranging
from that of a personal digital assistant to a supercomputer are all able to perform the same computational tasks so long as time and storage capacity are not
considerations.History of computing Main article: History of computingThe Jacquard loom was one of the first programmable devices.The Jacquard loom was one of the
first programmable devices.It is difficult to define any one device as the earliest computer. The very definition of a computer has changed and it is therefore
impossible to identify the first computer. Many devices once called "computers" would no longer qualify as such by today's standards.Originally, the term "computer"
referred to a person who performed numerical calculations (a human computer), often with the aid of a mechanical calculating device. Examples of early mechanical
computing devices included the abacus, the slide rule and arguably the astrolabe and the Antikythera mechanism (which dates from about 150-100 BC). The end of the
Middle Ages saw a re-invigoration of European mathematics and engineering, and Wilhelm Schickard's 1623 device was the first of a number of mechanical calculators
constructed by European engineers.However, none of those devices fit the modern definition of a computer because they could not be programmed. In 1801, Joseph Marie
Jacquard made an improvement to the textile loom that used a series of punched paper cards as a template to allow his loom to weave intricate patterns automatically.
The resulting Jacquard loom was an important step in the development of computers because the use of punched cards to define woven patterns can be viewed as an
early, albeit limited, form of programmability.In 1837, Charles Babbage was the first to conceptualize and design a fully programmable mechanical computer that he
called "The Analytical Engine".[2] Due to limited finance, and an inability to resist tinkering with the design, Babbage never actually built his Analytical
Engine.Large-scale automated data processing of punched cards was performed for the US Census in 1890 by tabulating machines designed by Herman Hollerith and
manufactured by the Computing Tabulating Recording Corporation, which later became IBM. By the end of the 19th century a number of technologies that would later
prove useful in the realization of practical computers had begun to appear: the punched card, boolean algebra, the vacuum tube (thermionic valve) and the
teleprinter.During the first half of the 20th century, many scientific computing needs were met by increasingly sophisticated analog computers, which used a direct
mechanical or electrical model of the problem as a basis for computation. However, these were not programmable and generally lacked the versatility and accuracy of
modern digital computers.Defining characteristics of five first operative digital computers Computer Shown working Binary Electronic Programmable TuringcompleteZuse
Z3 May 1941 Yes No By punched film stock Yes (1998)Atanasoff-Berry Computer Summer 1941 Yes Yes No NoColossus December 1943 /January 1944 Yes Yes Partially, by
rewiring NoHarvard Mark I/IBM ASCC 1944 No No By punched paper tape NoENIAC 1944 No Yes Partially, by rewiring Yes1948 No Yes By Function Table ROM YesA succession
of steadily more powerful and flexible computing devices were constructed in the 1930s and 1940s, gradually adding the key features that are seen in modern
computers. The use of digital electronics (largely invented by Claude Shannon in 1937) and more flexible programmability were vitally important steps, but defining
one point along this road as "the first digital electronic computer" is difficult (Shannon 1940). Notable achievements include:EDSAC was one of the first computers
to implement the stored program (von Neumann) architecture.EDSAC was one of the first computers to implement the stored program (von Neumann) architecture. *
Konrad Zuse's electromechanical "Z machines". The Z3 (1941) was the first working machine featuring binary arithmetic, including floating point arithmetic and a
measure of programmability. In 1998 the Z3 was proved to be Turing complete, therefore being the world's first operational computer. * The Atanasoff-Berry
Computer (1941) which used vacuum tube based computation, binary numbers, and regenerative capacitor memory. * The secret British Colossus computer (1944), which
had limited programmability but demonstrated that a device using thousands of tubes could be reasonably reliable and electronically reprogrammable. It was used for
breaking German wartime codes. * The Harvard Mark I (1944), a large-scale electromechanical computer with limited programmability. * The US Army's Ballistics
Research Laboratory ENIAC (1946), which used decimal arithmetic and was the first general purpose electronic computer, although it initially had an inflexible
architecture which essentially required rewiring to change its programming.Several developers of ENIAC, recognizing its flaws, came up with a far more flexible and
elegant design, which came to be known as the stored program architecture or von Neumann architecture. This design was first formally described by John von Neumann
in the paper "First Draft of a Report on the EDVAC", published in 1945. A number of projects to develop computers based on the stored program architecture commenced
around this time, the first of these being completed in Great Britain. The first to be demonstrated working was the Manchester Small-Scale Experimental Machine
(SSEM) or "Baby". However, the EDSAC, completed a year after SSEM, was perhaps the first practical implementation of the stored program design. Shortly thereafter,
the machine originally described by von Neumann's paper—EDVAC—was completed but didn't see full-time use for an additional two years.Nearly all modern computers
implement some form of the stored program architecture, making it the single trait by which the word "computer" is now defined. By this standard, many earlier
devices would no longer be called computers by today's definition, but are usually referred to as such in their historical context. While the technologies used in
computers have changed dramatically since the first electronic, general-purpose computers of the 1940s, most still use the von Neumann architecture. The design made
the universal computer a practical reality.Microprocessors are miniaturized devices that often implement stored program CPUs.Microprocessors are miniaturized devices
that often implement stored program CPUs.Vacuum tube-based computers were in use throughout the 1950s, but were largely replaced in the 1960s by transistor-based
devices, which were smaller, faster, cheaper, used less power and were more reliable. These factors allowed computers to be produced on an unprecedented commercial
scale. By the 1970s, the adoption of integrated circuit technology and the subsequent creation of microprocessors such as the Intel 4004 caused another leap in size,
speed, cost and reliability. By the 1980s, computers had become sufficiently small and cheap to replace simple mechanical controls in domestic appliances such as
washing machines. Around the same time, computers became widely accessible for personal use by individuals in the form of home computers and the now ubiquitous
personal computer. In conjunction with the widespread growth of the Internet since the 1990s, personal computers are becoming as common as the television and the
telephone and almost all modern electronic devices contain a computer of some kind.Stored program architecture Main articles: Computer program and Computer
programmingThe defining feature of modern computers which distinguishes them from all other machines is that they can be programmed. That is to say that a list of
instructions (the program) can be given to the computer and it will store them and carry them out at some time in the future.In most cases, computer instructions are
simple: add one number to another, move some data from one location to another, send a message to some external device, etc. These instructions are read from the
computer's memory and are generally carried out (executed) in the order they were given. However, there are usually specialized instructions to tell the computer to
jump ahead or backwards to some other place in the program and to carry on executing from there. These are called "jump" instructions (or branches). Furthermore,
jump instructions may be made to happen conditionally so that different sequences of instructions may be used depending on the result of some previous calculation or
some external event. Many computers directly support subroutines by providing a type of jump that "remembers" the location it jumped from and another instruction to
return to that point.Program execution might be likened to reading a book. While a person will normally read each word and line in sequence, they may at times jump
back to an earlier place in the text or skip sections that are not of interest. Similarly, a computer may sometimes go back and repeat the instructions in some
section of the program over and over again until some internal condition is met. This is called the flow of control within the program and it is what allows the
computer to perform tasks repeatedly without human intervention.Comparatively, person using a pocket calculator can perform a basic arithmetic operation such as
adding two numbers with just a few button presses. But to add together all of the numbers from 1 to 1,000 would take thousands of button presses and a lot of
time—with a near certainty of making a mistake. On the other hand, a computer may be programmed to do this with just a few simple instructions. For example:
mov #0,sum ; set sum to 0 mov #1,num ; set num to 1loop: add num, sum ; add num to sum add #1,num ; add 1 to num
cmp num,#1000 ; compare num to 1000 ble loop ; if num |
| | | How do I use the Speech tool on my computer to read articles on the intenet for me? (Answers: 4) | | Other - Computers | | There is this tool on the control panel which allows me to click on an article and read it for me, how do I do this? | i'm afraid those don't work very well. if everyone used style sheets and div tags to layout their pages those tools would work really well. but most web designers
are still laying out their pages with tables. tables will stop a text to speech program dead in it's tracks.even style sheets and div tags can stop one of those
programs if it isn't written correctly.until the majority web designers use style sheets it will remain a waste of time to use one of those.when you see articles
about web accessibility this is what they are talking about. |
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