...Computer From Wikipedia, the free encyclopedia Jump to: navigation, search For other uses, see Computer (disambiguation). "Computer technology" redirects here. For the company, see Computer Technology Limited. A computer is a programmable machine designed to sequentially and automatically carry out a sequence of arithmetic or logical operations. The particular sequence of operations can be changed readily, allowing the computer to solve more than one kind of problem. Conventionally a computer consists of some form of memory for data storage, at least one element that carries out arithmetic and logic operations, and a sequencing and control element that can change the order of operations based on the information that is stored. Peripheral devices allow information to be entered from external source, and allow the results of operations to be sent out. A computer's processing unit executes series of instructions that make it read, manipulate and then store data. Conditional instructions change the sequence of instructions as a function of the current state of the machine or its environment. The first electronic computers were developed in the mid-20th century (1940–1945). Originally, they were the size of a large room, consuming as much power as several hundred modern personal computers (PCs).[1] Modern computers based on integrated circuits are millions to billions of times more capable than the early machines, and occupy a fraction of the space.[2] Simple computers...
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...Discovering Computers 2011 Living in a Digital World Objectives Overview See Page 257 for Detailed Objectives Discovering Computers 2011: Living in a Digital World Chapter 5 2 Objectives Overview See Page 257 for Detailed Objectives Discovering Computers 2011: Living in a Digital World Chapter 5 3 What Is Input? • Input is any data and instructions entered into the memory of a computer Pages 258 – 259 Figure 5-1 Discovering Computers 2011: Living in a Digital World Chapter 5 4 What Is Input? • Instructions can be entered into the computer in the form of programs, commands, and user responses Pages 258 - 259 Discovering Computers 2011: Living in a Digital World Chapter 5 5 What Are Input Devices Page 260 Discovering Computers 2011: Living in a Digital World Chapter 5 6 The Keyboard • A keyboard is an input device that contains keys users press to enter data and instructions into a computer Page 260 Figure 5-2 Discovering Computers 2011: Living in a Digital World Chapter 5 7 The Keyboard • Most desktop computer keyboards have… Pages 260 - 261 Discovering Computers 2011: Living in a Digital World Chapter 5 8 The Keyboard • The insertion point, also known as the cursor, is a symbol on the screen that indicates where the next character you type will appear Page 261 Figure 5-3 Discovering Computers 2011: Living in a Digital World Chapter 5 9 The Keyboard ...
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...A computer is a programmable machine designed to sequentially and automatically carry out a sequence of arithmetic or logical operations. The particular sequence of operations can be changed readily, allowing the computer to solve more than one kind of problem. An important class of computer operations on some computing platforms is the accepting of input from human operators and the output of results formatted for human consumption. The interface between the computer and the human operator is known as the user interface. A computer is like a brain which can think, calculate, retrieve and organize information for its human master. This brain is supplied with parts that provide allow for input to it and allow it produce output for presentation to the one using it. Central Processing Unit The thinking part of the brain of the computer is the CPU or Central Processing Unit. This component provides all the control and manages calculations and manipulation of data. Computer manufacturers are always trying to squeeze more speed and multiprocessing capability (doing multiple things at the same time) out of it. This has led to the dual core or multiple core CPU which is popular today. A core is basically a computer so that a dual core computer is really 2 computers in one. Computer speed is usually measured in GHz which means Gigahertz which in turn mean billions of cycles per second. The basic idea is that the higher the number of cycles, the faster the computer is. Today the...
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...A BRIEF COMPUTER HISTORY The computer as we know it today had its beginning with a 19th century English mathematics professor name Charles Babbage. He designed the Analytical Engine and it was this design that the basic framework of the computers of today are based on. Generally speaking, computers can be classified into three generations. Each generation lasted for a certain period of time,and each gave us either a new and improved computer or an improvement to the existing computer. First generation: 1937 – 1946 - In 1937 the first electronic digital computer was built by Dr. John V. Atanasoff and Clifford Berry. It was called the Atanasoff-Berry Computer (ABC). In 1943 an electronic computer name the Colossus was built for the military. Other developments continued until in 1946 the first general– purpose digital computer, the Electronic Numerical Integrator and Computer (ENIAC) was built. It is said that this computer weighed 30 tons, and had 18,000 vacuum tubes which was used for processing. When this computer was turned on for the first time lights dim in sections of Philadelphia. Computers of this generation could only perform single task, and they had no operating system. Second generation: 1947 – 1962 - This generation of computers used transistors instead of vacuum tubes which were more reliable. In 1951 the first computer for commercial use was introduced to the public; the Universal Automatic Computer (UNIVAC 1). In 1953 the International Business Machine (IBM)...
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...Hardware Theft and Vandalism Hardware theft and vandalism are other types of computer security risks. Hardware theft is the act of stealing computer equipment. Hardware vandalism is the act of defacing or destroying computer equipment. Hardware vandalism takes many forms, from someone cutting a computer cable to individuals breaking into a business or school computer lab and aimlessly smashing computers. Companies, schools, and other organizations that house many computers are at risk of hardware theft and vandalism, especially those that have smaller system units that easily can fit in a backpack: briefcase. Mobile users also are susceptible to hardware theft. It is estimated that more than 600,000 notebook computers are stolen each year. The size and weight of these computers make them easy to steal. Safeguards against Hardware Theft and Vandalism To help reduce the chances of theft, companies and schools use a variety of security measures. Physical access controls, such as locked doors and windows, usually are adequate to protect the equipment. Many businesses, schools, and some homeowners install alarm systems for additional security. School computer labs and other areas with a large number of semi-frequent users often attach additional physical security devices such as cables that lock the equipment to a desk, cabinet, r floor. Small locking devices also exist that require a key to access a hard disk or optical disc drive. Some businesses use a real time location...
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...ROLE OF COMPUTERS About two hundred years before, the word "computer" started to appear in the dictionary. Some people even didn't know what is a computer? However, most of the people today not just knowing what is a computer, but understand how to use a computer. Therefore, computer becomes more and more popular and important to our society. We can use computer everywhere and they are very useful and helpful to our life. Computers have brought about a tremendous revolution in every walk of life and are expected to open more vast fields due to the dexterity of those who design software and those who develop application programs. In a very short period, scientists have been able to extirpate all the defects, the limitations and the shortcoming of computer and much is expected from their ingenuity, acumen and acquisitiveness. The fields of application of computers are various and new applications are being searched out. The scientists applied it to prediction of weather earthquakes, and storms, controlling of satellites and controlling of atomic reactions in reactors and else where. Engineers have not lagged behind. They use computers in designing cars aeroplanes, ships, buildings, bridges and tools etc. In the business world, computers are playing great parts. They are used to word processing, record keeping, inventory controlling, patrol processing, account keeping and auditing, stock marketing and ticket reservations. They are now used to keep personal telephone and address...
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...Input and Output Devices The devices which are used to input the data and the programs in the computer are known as "Input Devices". or Input device can read data and convert them to a form that a computer can use. Output Device can produce the final product of machine processing into a form usable by humans. It provides man to machine communication. Before a computer can process your data, you need some method to input the data into the machine. The device you use will depend on what form this data takes (be it text, sound, artwork, etc.). Similarly, after the computer has processed your data, you often need to produce output of the results. This output could be a display on the computer screen, hardcopy on printed pages, or even the audio playback of music you composed on the computer. The terms “input” and “output” are used both as verbs to describe the process of entering or displaying the data, and as nouns referring to the data itself entered into or displayed by the computer. Below we discuss the variety of peripheral devices used for computer input and output. Input Devices Keyboard: The computer keyboard is used to enter text information into the computer, as when you type the contents of a report. The keyboard can also be used to type commands directing the computer to perform certain actions. Commands are typically chosen from an on-screen menu using a mouse, but there are often keyboard shortcuts for giving these same commands. In addition...
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...Computers types I, Computer: Definition A computer is a machine that can be programmed to manipulate symbols. Its principal characteristics are: § It responds to a specific set of instructions in a well-defined manner. § It can execute a prerecorded list of instructions (a program). § It can quickly store and retrieve large amounts of data. Therefore computers can perform complex and repetitive procedures quickly, precisely and reliably. Modern computers are electronic and digital. The actual machinery (wires, transistors, and circuits) is called hardware; the instructions and data are called software. All general-purpose computers require the following hardware components: § Central processing unit (CPU): The heart of the computer, this is the component that actually executes instructions organized in programs ("software") which tell the computer what to do. § Memory (fast, expensive, short-term memory): Enables a computer to store, at least temporarily, data, programs, and intermediate results. § Mass storage device (slower, cheaper, long-term memory): Allows a computer to permanently retain large amounts of data and programs between jobs. Common mass storage devices include disk drives and tape drives. § Input device: Usually a keyboard and mouse, the input device is the conduit through which data and instructions enter a computer. § Output device: A display screen, printer, or other device that lets you see what the computer has accomplished. In addition to these components...
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...The History of Computers http://inventors.about.com/library/blcoindex.htm "Who invented the computer?" is not a question with a simple answer. The real answer is that many inventors contributed to the history of computers and that a computer is a complex piece of machinery made up of many parts, each of which can be considered a separate invention. This series covers many of the major milestones in computer history (but not all of them) with a concentration on the history of personal home computers. Ads Cars - Motor Traderwww.motortrader.com.myBuy and Sell New Cars, Used Cars You Can Find 15000+ Cars From Here! BGS Repair Servicewww.lelong2u.comRepair/Sales/Buy/Used-Projector,LCD Laptop,Server,PC,Printer and iMAC. Network Traffic Shapingwww.exinda.comVisibility of all Applications. Traffic Shaping for WAN & Web. Computer History Year/Enter | Computer History Inventors/Inventions | Computer History Description of Event | 1936 | Konrad Zuse - Z1 Computer | First freely programmable computer. | 1942 | John Atanasoff & Clifford Berry ABC Computer | Who was first in the computing biz is not always as easy as ABC. | 1944 | Howard Aiken & Grace Hopper Harvard Mark I Computer | The Harvard Mark 1 computer. | 1946 | John Presper Eckert & John W. Mauchly ENIAC 1 Computer | 20,000 vacuum tubes later... | 1948 | Frederic Williams & Tom Kilburn Manchester Baby Computer & The Williams Tube | Baby and the Williams Tube turn on the memories...
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...Computer and our life Importance of computer: Computer is an important machine in our life. Without computer our life is nothing. We need to use it in every sector of our life. What type of work sector that is we are using computer. It makes our job easier and simple. Computer creates a great opportunity for us. We are changing our life style quickly through computer. We are using it in education sector, medical sector, research and experimental job, designing, architectural designing, planning, public administration and etc. Computer changed our education system. We can learn through long distance education system. Now we do not need to go far from home to learn something. We can save our time and money by this. Without that we are able to get every service at home. Computer is also able to provide us another service. Now doctor can do operations through computer. It resumes risk for a patient. Doctors do not need to work more. Computer also helps us in research like educational, scientific, medical and etc. Really, computer is a great invention of human life. Computer and communication: ------------------------------------------------- Without helping in our work we can communicate through computer. Now-a-days computer is the powerful communication media. Generally it communicates through network and internet is the well known network system. We can talk, chat, mail through computer. We can keep contract with international community by internet. E-mail is a blessing...
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...ages before, when there were no computers or any other technologies. So much we have advanced that now every information is just a click away and is in your hands 24/7. All this advancement was possible only with the introduction of a small device called the “Computer”. Computers Image Curtsey: csntrust.org.nz/attachments/Image/PC-picture-1.jpg?1367216528141 Basically, computer is a device that accepts the message by the imputer and processes this message and stores the information at the storage devices and later gives an output of the message through the output devices. A simple explanation of the computer. Normally, a computer consists of a processing unit called the Central Processing Unit or the CPU and a form of memory. In the years between 1940 and 1945 were the first electronic digital computers developed. The initial sizes were as big as a room and consumed power as much as today’s personal computers. Initially, computer was related to a person who carries out calculations or computations and as such the word computer was evolved in 1613 and continued till the end of 19th century. Later it as re-described as a machine that carries computations. The early computers were limited in their functions. It was the fusion of automatic calculation and programmability that produced the first computers that were recognized in 1837. Charles Babbage in 1837 was the first to introduce and design a fully programmed mechanical computer, his analytical engine. Due to limited...
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...Running head: COMPUTER CRIME 1 Computer Crime and the 4th Amendment ITT Technical Institute COMPUTER CRIME 2 The case law that would allow me to search the office computer of Jacob Myers would be the 4th Amendment law and also The Wire and Electronic Communications Interception and Interception of Oral Communications Act. Under the 4th Amendment to do a search and seizure you need to have probable cause. Under The Wire and Electronic Communications Interception and Interception of Oral Communications Act it typically requires a court order issued by a judge who must decide that there is probable cause to believe that a crime has been, is being or is about to be committed. In this case we do have probable cause because the victim, Cynthia Simmons had to countless number of times change her email, IM, and internet provider; during a preliminary investigation we scanned the victims computer and found a key logging program was being used to collect the victims information and stalk the victim. And upon our investigation, posing as the victim the offender once again sent the victim a message via IM. That conversation allowed the officers to trace the computer to the offender’s job at the probation department. So because the suspect Jacob Myers works at the probation department and he has been the one previously stalking the victim there is enough probable cause to search his work computer and put surveillance because now he is...
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...Discovering Computers 2011 Chapter 4 DISCOVERING COMPUTERS 2011 CHAPTER FOUR: THE COMPONENTS OF THE SYSTEM UNIT PROBLEM SOLVING TIP SHEET Use this Tip Sheet as suggested starting points for the Problem Solving exercises. Problem Solving @ Home 1. Malfunctioning Speakers While working on a homework assignment, you decide to listen to one of your favorite music CDs through your computer speakers. The media player program on your computer automatically starts when you insert the CD. Although it looks like the CD is playing, no sound is coming from your speakers. What might be causing this? What is the first step that you will take to correct this problem? The sound might be muted or the volume turned down; adjust accordingly There may be a problem with your computer recognizing the sound card; check the drivers 2. Optical Disc Drive Stuck While using your computer, you attempt to open the optical disc drive to insert an installation disc for a program you wish to install. The drive, however, does not open when you press the eject button. The drive opened a few minutes prior, when you removed a music CD. What steps will you take to open the drive before calling technical support? Restart the computer. If the problem persists after restarting the computer, shut the computer down and insert the end of a paperclip into the small hole in the optical disc drive (if one exists) to open the drive manually. If necessary, check with technical support or your computer’s documentation...
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...The computer is one of the most brilliant gifts of science. This device was originally developed by Charles Babbage. Most countries have developed fast due to computerization. Writing a program is essential for a computer. Speed, accuracy, reliability, and integrity are the main characteristics of a computer. Many of the routine activities today at home and in business are done by computers. The computer has proved a friend and servant of science, technology and industry. Most offices, shops, factories and industries use computers. The Internet is a storehouse of information. The computer is a boon to all. Telecommunication and satellite imageries are computer based. Computers have made the world a global village today. The computer is one of the most brilliant gifts of science. It is an electronic device for storing and analyzing information fed into it, for calculating, or for controlling machinery automatically. Charles Babbage developed this device first in 1812 followed by George Boole in 1854, Howard and Aitten in 1937, Dr. John Nouchly and J. P. Eckert in 1946. These computers were named the first generation equipment. Today, wit the 'Artificial Intelligence' technology, we are using fifth generation computers. Each new generation of computers has been smaller, lighter, speedier and more powerful than the earlier ones. Now note-book sized computers like laptop are fairly common. Computers have been dominating technology since 1970s, and has now entered almost all walks...
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...attenuation. If, for example, you have a thin Ethernet network with a cable segment longer than the prescribed maximum of 185 meters, you can install a repeater at some point in the segment to strengthen the signals and increase the maximum segment length. This type of repeater only has two BNC connectors, and is rarely seen these days. 8 Port mini Ethernet Hub The hubs used on UTP Ethernet networks are repeaters as well, but they can have many RJ45 ports instead of just two BNC connectors. When data enters the hub through any of its ports, the hub amplifies the signal and transmits it out through all of the other ports. This enables a star network to have a shared medium, even though each computer has its own separate cable. The hub relays every packet transmitted by any computer on the network to all of the other...
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