Computer hardware

Hardware represents the physical and tangible components of the computer itself i.e. components which can be seen and touched. It includes

• Input devices.
• Output devices.
• Central Processing Unit.
• Memory.

All input and output devices connected to computers are collectively known as peripherals.

Input Units:

Input units provide communication between man and machine. Input of any form from input device is converted into binary signals so that it can be understood by CPU. This process is known as digitizing. Input data may be text, graphics, audio, video or combinations.

Some Common Computer Input Devices:

Keyboard

Used to type data into the computer Most common input device today

Has special keys for giving the computer commands. Commands tell the computer to do something, like save the file. These special keys are called command or function keys.

Pointing Devices

Pointing devices move some object on the screen and can do some action. Common pointing devices are mouse, track ball, game consoles etc.

Scanner

A scanner allows you to scan documents, pictures, or graphics and view them on the computer. You can also use software to edit the items you scan.

• Used to put printed pictures and text into a computer.
• Converts an image into dots that the computer can understand.
• To scan text, optical character recognition (OCR) software is needed.

Digital Camera

• Used to take electronic pictures of an object.
• The pictures taken by a digital camera can be used directly by a computer.

Microphone

• Used to put sound into a computer.
• Need sound recording software Scanner.

CD/DVD-ROM

• Can be used to put both sound and images into a computer.
• Use a laser to read a Compact Disk (CD) or a DVD disk.

Video Capture Card

• Usually place inside the computer's case.
• Use to put video into a computer.
• Need a video source, either a video camera or video recorder.

Central Processing Unit (CPU):

CPU is the brain and heart of a computer. It runs user input instructions, processes them and finally provides the output.

Today, all CPUs are microprocessors

• A microprocessor is a complete computer on a silicon chip.
• A microprocessor does all of the functions of a computer.
• Stores data and instructions waiting to be used.
• Follows changeable instructions.
• Does input, processing, and output.

CPU has three major component Arithmetic and Logical Unit (ALU), Control Unit (CU) and Memory Unit (Registers).

The Arithmetic and Logic Unit (ALU) carries out all mathematical and logical operations in a computer.

The Control Unit directs the flow of information into the CPU and /or memory or storage. It controls which instructions the CPU will do next.

Memory units in a CPU are known as Registers. These are small memory locations of definite size which stores data and instructions on temporary basis for processing.

The size of the registers are given by the word length which in turn is expressed by no of bits making a word. The size of the register directly determines the speed and performance of a processor. Speed of a CPU

• The speed of a CPUs is measured in hertz (Hz).
• A hertz is one cycle per second.
• All computers possess built in clocks for timing the cycles.
• The clock is usually located in a small metal box on the motherboard.
• Today, many CPUs can complete over six (6) instructions per second.
• Contemporary microprocessors can operate with speed of around 2 gigahertz.
• 1 giga hertz (GHz) = 10⁹Hz

Output Units:

Output devices are used to provide output to environment. The output coming from the CPU is in theorem of electronic binary signals which needs conversion in the form which can be understood by human being.

The output can be provided to monitor screen or visual display units, printers, plotters, loaders and speech synthesizers etc.

Some Common Output Devices:

Monitors and Displays

• Shows the processed information on a screen.
• A monitor or display produce a soft copy. When the device is turned off the information goes away.
• Monitors are slowly being replaced by flat panel displays.

Printers

• Printers produce a hard copy.
• The information is printed on paper and can be used when the device is off.
• It is also called a printout.

Speakers

• used to output sound

Memory:

Memory is used for storing information's. It is mainly classified into two type's internal memory and External memory. The internal memory is further classified into CPU and Main memory. CPU memory is registers and on chip cache. Main memory is classified as Random Access Memory (RAM) and Read Only Memory (ROM).

External memory is the attached or extended memory. Magnetic disk, Magnetic tape and optical disk are coming under these categories.

Some Common Storage Devices

Hard Drive

The hard drive is the primary device that a computer uses to store information. The hard drive stores programs, data files, saves files, and organizes files. The hard drive is located inside the computer case. The hard drive, magnetically stores data on stacks of rotating disks called platters.

Floppy Drive

The floppy drive stores and retrieves information on a floppy disk.

CD -ROM Drive

CD-ROM is a device that reads information stored on a compact disc. CD- ROM stands for Compact Disc Read Only Memory. One CD is equal to the space in over 40 floppy disc.

Removable Hard Disk

A zip disk is a removable disk that holds a large amount of information. A zip disk can be used to achieve, protect and transfer large amounts of data.

Computer software

A computer cannot do anything on its own. It must be instructed to do a desired to do a desired job. Hence, it is necessary to specify a sequence of instructions, which a computer must perform to solve a problem. Such a sequence of instructions, written in a language, which can be understood by a computer, is called a computer program. It is the program, which controls the activity of processing by the computer, and the computer performs precisely what the program wants it to do. When a computer is using a program, we say, it is running or executing that program. The term software is refers to the set of computer programs, procedures, and associated documents (flowcharts, manuals, etc.), which describes the programs, and how they are to be used. To be precise, software means a collection of programs, whose objective is to enhance the capabilities of the hardware. A software package is a group of programs, which solve a specific problem or perform a specific type of job. For example, a word-processing package may contain programs for text editing, text formatting, drawing graphics, spelling checking, etc. Hence, a multipurpose computer system has several software packages, one each for each for every type of job it can perform.

Website

A Web site is a related collection of World Wide Web (WWW) files that includes a beginning file called a home page. A company or an individual tells you how to get to their Web site by giving you the address of their home page. From the home page, you can get to all the other pages on their site. For example, the Web site for IBM has the home page address of http://www.ibm.com. (The home page address actually includes a specific file name like index.html but, as in IBM's case, when a standard default name is set up, users don't have to enter the file name.) IBM's home page address leads to thousands of pages. (But a Web site can also be just a few pages.)
Since site implies a geographic place, a Web site can be confused with a Web server. A server is a computer that holds the files for one or more sites. A very large Web site may be spread over a number of servers in different geographic locations. IBM is a good example; its Web site consists of thousands of files spread out over many servers in world-wide locations. But a more typical example is probably the site you are looking at, whatis.com. We reside on a commercial space provider's server with a number of other sites that have nothing to do with Internet glossaries.
A synonym and less frequently used term for Web site is "Web presence." That term seems to better express the idea that a site is not tied to specific geographic location, but is "somewhere in cyberspace." However, "Web site" seems to be used much more frequently.
You can have multiple Web sites that cross-link to files on each others' sites or even share the same files.

Internet

The Internet is an advancement, which holds numerous opportunities and privileges for everyone. Individuals, companies, and institutions use the Internet in many ways. Businesses use the Internet to provide access to complex databases. Companies carry out electric commerce, including advertising, selling, buying, distributing products, and providing after-sale services (Ater, 27).

Businesses and institutions use the Internet for voice and video conferencing and other forms of communication that enable people to telecommute or work from a distance. The use of e-mail over the Internet has greatly speeded communications between companies, among coworkers, and between other individuals. Media and entertainment companies use the Internet to broadcast audio and video, including live radio and television programs. These companies also offer on-line chat groups, in which people carry on discussions using written text and voice communication. People use the Internet for communication, entertainment, finding information, and also to buy and sell goods and services. The Internet is a global computer network allowing communication with millions of computer users and access to virtually anything around the world. The positive progression of communication is an outstanding necessity to this day and age. Computer use has increased dramatically and it has now become possible for everyone to be able to afford to purchase a computer.

The creation of the computer and Internet has affected businesses in many positive ways. These applications are a successful establishment in a business setting. Both deliver quality management capabilities and serve the international standard for businesses and industries around the world. They have an enormous impact on human communication. Computers in a business setting serve the role of communication amongst others inside and outside of the company. Both of these applications (computers and the Internet) also provide a business with capabilities to broadcast ideas quickly and efficiently.

The Internet's broadcasting abilities are considered to be very wide spread. The most obvious applications of the Internet are sales/marketing and data management, which is the process of organization that is designed to simplify a system while still maintaining the flexibility that can be easily adapted to anyone's specific needs. The growth of the Internet has made communication with remote locations such as district offices, outside sales staff, etc. more efficient than ever before.
Advertising on the Internet has been increasing and is viewed while surfing, reading e-mail, and spending time on the web in general. We are probably exposed to about 35 'pop-up' ads continuously, one after another, just by simply entering a single web site. By my own personal experience, I find it distracting when I enter a web site and am surrounded with several advertisement windows that take forever to close even after you have left the web site. By the time I am actually finished closing all of the Advertising campaigns use specific images to manipulate the consumer into believing they must have a specific product. It is very easy to get side tracked when you see an advertisement you are interested in and would like to know more about. Advertising abilities vary from banner style advertisements to game imaged ones that encourage you to play a game and win a prize. It has been said that the primary form of advertising on the web (ex: banner form ads) has proven notoriously ineffective at generating clicks. This can be looked at in a positive and negative way. The positive viewpoint is the fact that negative feedback from a bad advertisement simply means it needs more work. Direct response advertising, (such as ads that suggest 'click here' for more information or my personal favorite: Punch the monkey and win $20 instantly, as seen on msn.com.) allow advertisers to find out how effective/ineffective a given advertisement actually is. The negative aspect is the actual hard work of trying to figure out exactly how to attract people and get them to respond to your ad.

According to recent research, the number of online users in the US is expanding rapidly. In addition, within the last year, online commerce (which is considered to be the large scale buying and selling of goods and services) transactions have become commonplace (Einstein, 21). This given statement is another excellent reason why the Internet and computers are a positive advancement for businesses. When customers go on-line, they are most often looking for information on specific types of products or trying to find savings on products they need. This is clearly a booming potential market and one that will significantly impact the way that advertising and commerce is conducted over the upcoming years.

-"Approximately 64.2 million US adults (32.5 percent of the adult population) currently use the Internet, according to the Spring 1999 CyberStats report from Mediamark Research, Inc." (Almost 65 Million Americans Online, cyberatlas.internet.com, May 1999)-"According to EMarketer's ECommerce Study], by year-end 1999, the number of online buyers will double to 36.1 million, or 16.6 percent of the U.S. population 14 and older. By the year 2002, eMarketer says the U.S. will have 63.7 million online buyers, representing nearly one-third or 28.4 percent, of all Americans 14 and older. "
(Online Buyers to Double by the End of 1999, cyberatlas.internet.com, December 1998)

- "EMarketer has found that ... 33.1 million [web users] are 'window shopping' -- browsing, researching, and comparison shopping for goods and services over the web."
(Online Buyers to Double by the End of 1999, cyberatlas.internet.com, December 1998)
[Quotes and estimates received by: www.townvalues/advantages.com]

There have nearly been 407.1 million people, which were estimated to access the Internet as of November 2000. This is a global figure, which also highlights the fact that the Internet is the one medium, which can be used to reach every city and every country over the globe. It means your business does not just have to concentrate on local markets meaning anything is possible.The Internet represents one of the most successful examples of worldwide communication, which involves the interaction of people and their computers, despite their location. If a business has a web site, this in itself means it is accessible by the global market, and it is vital that this business takes advantage of this. Your businesses web site has the ability to be viewed from all over the country and world. The only way to market globally is via the Internet, and the only way to accomplish that, is with a computer. The computer and Internet provide us with the ability to promote locally and globally. Normal media advertising and promotion (such as through magazines, radio and local promotions) cannot gain as much traffic as marketing on the Internet can.

An advantage of advertising on the web is the fact that there are hundreds, possible thousands of places where you can advertise for free on the Internet. You just have to know where to find them. This is a valuable resource for a new person just starting out without a lot of money, looking for more exposure for their business.

When first starting off a business, you need all the publicity it can possibly receive. As long as these free sites are available, they will be used. With out the existence of computers and the Internet, this option would never be possible. By bringing more exposure to your site you gain another method of promotion that excels more that what television, newspapers and radio have to offer.

The creation of the computer and Internet has held an important role in intercommunication within a company. The 'distance learning' process, reveals a widespread interest in using the Internet for education-from-home. Distance learning is a process of learning from home by means of video instruction and e-mail. It involves teaching or learning a skill for a job. For instance, instead of paying for a group of employees to attend a training seminar, you are able to produce an 'at work/home' seminar, subtracting the travel fees, which will in the long run, save your business money.

The Internet has contributed to the success of small businesses in the international market. Early hopes of Internet-based commerce have not proven themselves to be the route that such commerce was expected to take, but the growth of the Internet and its associated technology have become the lifeblood of many businesses that otherwise would have remained tabletop businesses with only local influence (Einstein, 37). The most successful Internet ventures have been products over services, but each has seen growth. The arrival of the secure electronic transaction has relieved the fears of many who formerly were would-be purchasers that have now joined the growing numbers of consumers and businesses taking advantage of the opportunities of the Internet. Many people are beginning to over come the apprehension of ordering products on-line. It is something that has gradually become safer and more efficient.

Though the Internet has not reached its full potential as a sales tool, it is
heading resolutely in that direction, and to the point that those companies not offering extensive online options to their existing customers may lose those customers to businesses that do.

The computer and the Internet have proved to enhance our capabilities within a business. It has given us the power to advertise on-line and be viewed by anyone in the world that owns a computer and a modem. These advances have affected businesses by the ways of advertising, communication within a company, distance learning, and on-line commerce and data management.

The topics explained in this paper are only a few of the many advances that the computer and the Internet have to offer for a business. The computer's abilities in a business setting are wide spread. Computers have the ability to be upgraded which allow them to produce a powerful newer version of the latest software, which saves money by not having to buy brand new PC's anytime a new advancement is discovered. Utilizing the advances of both hardware and software are important to business quality and production. Computers are time savers, by the means of 'spell check' and Excel spreadsheets that do the work for you by simply entering a formula for it to follow. You even have the ability to turn your PC into a fax machine with the right software, which is actually cheaper then buying your own fax machine, which can cost hundreds. Keeping up with current technology is difficult, but necessary, task for all businesses. Faxing over your PC is a small, but important step in helping the environment conserve paper. You can even make a phone call by using your computer. Web sites such as dialpad.com or I-link.com allow this as long as you have a microphone.

Technology makes it easier to accessing information such as handling customer profile information, company-wide inventory accounting, inventory control & product information, and more (Alter, 42). Computers, in conjunction with Internet use, organize data, structure it, and present it in a way that can be easily utilized. The impact of increased use of these applications has an influence of how a company or business will succeed and progress.

Computer chips

Computer Chips

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Thanks to the many applications and appliances that have come from the computer chip Americans have become less dependent on themselves and more dependent on automation. This, in turn, has produced a lazier generation with an inferior work ethic. Creating increased reliance on a piece of silicon rather than using their own brain. The simple but powerful computer chip has shortened the existence of man.


Many humans could not live without the computer chip. People have become so dependent on computer chips to control fax machines to send work, take in and process information on computers, and doctors who use all types of machines that are controlled by computer chips to diagnose symptoms. Although there are promising applications for computer chips, they have taken the jobs of many Americans. In the past many assembly lines were done manually with people putting the pieces together. Now many assembly lines are computer controlled by a computer chip. It also use to be that people did simple things for them selves, such as water the garden or mow the lawn. Now when requested by parents to their teenager the teenager is more apt to find a effortless and automated way to get the chore done. In this situation the teenager might suggest the easy way out by saying let the automated computer chip controlled water sprinkler take care of it. Or in the case of mowing the lawn the teenager might use a robotic lawn mower which is controlled by a computer chip to cut the grass. While they stay in the house sitting on the couch watching t.v.


It runs cars, it powers computers, and helps Americans through everyday life. The computer chip has become as essential to human existent just as air or water. Today humans use computer chips hundreds of times a day without thinking twice.

Laptop

  People of today often find difficulty in deciding whether they will purchase a desktop computer or a laptop computer. It may seem that the two are similar but they are totally different. The purpose of this essay is to compare and contrast the differences of desktop computers and laptop computers in terms of convenience, maintenance, performance and cost.

          As we all know, a desktop computer is hard to move and it is cluttered due to many wires and cables that need to be connected to each other. Speakers, keyboard and mouse for a laptop computer is built-in so it does not contain wires. It is quite annoying to see so many wires and cables in a desktop computer. The laptop computer is also portable. You can move it with you while you travel and it just occupies a small space.

          Performance of a laptop computer and a desktop computer has great differences. The desktop computer is capable of having better components that can handle better graphics. It is suitable for hardcore gaming. All the components of a computer are much better for the desktop computer. On the other hand, a notebook has its limits. Even though it can handle some computer games, it cannot handle hardcore games which are new releases. Its battery is also limited and easily overheats in just a short time unlike the desktop computer which does not overheat easily unless you keep it turned on for a very long time – about three days without turning it off if placed in a well ventilated place or overclocking it (Marlene, 2009).

          Maintenance is a great factor in choosing what type of computer you will go for. A desktop computer is easy to customize. You can easily choose what brand or how powerful each component is. On the other hand, a notebook is always sold as a whole. It is also difficult to upgrade. You will need to use your USB port if you want to upgrade its hard drive and it is annoying to have it outside of your notebook. If a notebook is damaged, you will need to replace it as a whole and you are lucky if it is still under warranty. But if a desktop computer gets damaged, you can just replace the parts of it that have been damaged.

          Another factor in choosing between a laptop and a desktop is its cost. According to Null(2007), a desktop computer’s price is cheaper than a notebook because it can be 25% - 50% more powerful than a notebook given a price. The only downside in purchasing a desktop computer is that it consumes more energy than a notebook because it has many components. The problem in a laptop is that it can be stolen easily. If this happens, you will need to buy another one as a replacement.

Desktop

  People of today often find difficulty in deciding whether they will purchase a desktop computer or a laptop computer. It may seem that the two are similar but they are totally different. The purpose of this essay is to compare and contrast the differences of desktop computers and laptop computers in terms of convenience, maintenance, performance and cost.

          As we all know, a desktop computer is hard to move and it is cluttered due to many wires and cables that need to be connected to each other. Speakers, keyboard and mouse for a laptop computer is built-in so it does not contain wires. It is quite annoying to see so many wires and cables in a desktop computer. The laptop computer is also portable. You can move it with you while you travel and it just occupies a small space.

          Performance of a laptop computer and a desktop computer has great differences. The desktop computer is capable of having better components that can handle better graphics. It is suitable for hardcore gaming. All the components of a computer are much better for the desktop computer. On the other hand, a notebook has its limits. Even though it can handle some computer games, it cannot handle hardcore games which are new releases. Its battery is also limited and easily overheats in just a short time unlike the desktop computer which does not overheat easily unless you keep it turned on for a very long time – about three days without turning it off if placed in a well ventilated place or overclocking it (Marlene, 2009).

          Maintenance is a great factor in choosing what type of computer you will go for. A desktop computer is easy to customize. You can easily choose what brand or how powerful each component is. On the other hand, a notebook is always sold as a whole. It is also difficult to upgrade. You will need to use your USB port if you want to upgrade its hard drive and it is annoying to have it outside of your notebook. If a notebook is damaged, you will need to replace it as a whole and you are lucky if it is still under warranty. But if a desktop computer gets damaged, you can just replace the parts of it that have been damaged.

          Another factor in choosing between a laptop and a desktop is its cost. According to Null(2007), a desktop computer’s price is cheaper than a notebook because it can be 25% - 50% more powerful than a notebook given a price. The only downside in purchasing a desktop computer is that it consumes more energy than a notebook because it has many components. The problem in a laptop is that it can be stolen easily. If this happens, you will need to buy another one as a replacement.

Computer

Computer is an electronic device which can take input from the user and process this input data and if need, store data or information on storage devices and give output on output devices. It follow the instructions us it is which we input. It takes input through Keyboard, mouse, etc and then it processes the input data and give output on display screen and store data if need.

Desktop Computer:-

Mostly called personal computer (PC), design to fit completely on a typical desk of office or home. It mainly comes with a monitor, a minitower or horizontal casing. Today, mostly
Casing contains processor, hard disk in gigabytes, built-in modem, LAN port, USB ports and CD-ROM. Over the past few years. CPU processing speed has been increasing processing speed can be increase by adding capable RAM, capable BUS, high processor which have high processing cycle, hence more heat is also produced we use heat sinks and fans for the removal of heat from the computer as higher temperature can cause severe damage to the computer, fans are noisy and aren’t much effective so the new trend is liquid cooling. It’s just like a radiator installed for cooling, a liquid is circulated in the heat sink attached to the processor heat is transferred from the processor to the liquid is then transferred to the radiator the liquid is cooled down there and then again circulated to the heat sink. It’s less noisy as compared to fan as high speed processor clocked at higher speed need fan rpm over 7500. This new trend is helpful for the people who want to over clock their processors. Over clocking means to gain higher speed from the same processor, or running the processor at extreme level in which cooling come as very important factor.

Laptop Computer:-

Laptop is a portable computer which can be easily used on lap. Small enough to fit in briefcase mostly called “notebook”. It can run directly by electric source or on batteries. Most of laptop weighs less than five pounds and are less than three inches thick.  Laptop mostly cost more than desktop computers with same specifications, because they are difficult to build than desktop computer.
It contains almost things which are in desktop but have built-in LCD, keyboard and mouse. New technology which is introduced in laptop is PROCESSOR: Core i7-2600K Quad Core, DDR3 SDRAM with a memory clock frequency of 100 MHz gives a maximum rate of transfer of 6400 MB per second. Now introduce DDR4, SDRAM.  HARD DISK: Seagate Barracuda 1.50TB internal hard drive. BATTERY: Micromanagement miraculous battery 12-hours timing, GAMING GRAPHICES: NVIDIA before GTX 400m series. Another new trend is of gaming laptops let’s take an example of the new alien ware m11x the most powerful 11inch desktop with 1gb NVIDIA 335M graphics, with 7 hours of battery time with Nvidia Optimus graphics switching technology, DDR3 ram.

Nepal

My small country Nepal attributing an angelic beauty is situated between two large countries called china in north and India in three sides.According to the census report of 2001 A.D the population of country Nepal is 2,31,51,423 and its area is 1,47,181.The population density of Nepal is 154 people in per sq.km but the valley and the plains are densely populated.
Nepal is a agro based country.Eighty percent of the people of Nepal are depend upon the agriculture .Although the people of various social group,various religions,they really practice "unity in diversity".The follower of one religion respect the follower of the another religion.Most of the people of the Nepal follow the Hindu religion,and rest of the people follow the religion like Muslim,Christian,Buddha etc.
Nepal is popular for the angelic beauties ,unique wonders and gifts in the world,although it is a land locked country.It is famous for river lakes and mountain.Tourist come here for relaxation in their holiday.The highest mountain peak Mount Everest in the world,fascinates many foreign tourist everyday.Through tourism we can earn foreign money which can be invest in development project.Nepal is rich in water resources it is the second richest country in water in the world.Many rivers flow from the mountain and it passes through the terai.Many brooks and stream serves the people in many ways.They are advantageous for irrigation,transportation,rafting,running hydroelectricity projects and so on.
It is said that "Hario Ban Nepal Ko Dhan".In fact we can get many advantages from the forest.Our country Nepal seems to be beautiful because of the green forest,but nowadays forest is being destroyed in many ways .But also many awareness program are conducted.National parks and wild-life reserves preserve many wild animals .Many tourist come here to watch them.
Nepal is a developing country .About 50%of the Nepalese people are literate .Many school and colleges have been running all over the country .Due to high percent of poverty Nepal many children do not go to school .
I feel proud to be the citizen of Nepal like country.We Nepali people respect each other.We are co-operative .I do feel most of the people love the nation.We feel the mother and mother lands are same .I do hope that our country Nepal will be best and famous country in the world.

Basic Computer Course

Basic computer course is a course that we slowly get the knowledge about computer to use it. If we get the knowledge about the computer then we can know definition of computer. In basic course there is many lessons that we have to study like MS Word, Excel, Powerpoint, Paint, Typeshalla, etc. First of all we have to study how type for this we have to use typeshalla because typeshalla help us to improve our typing then we can use Ms Word, Excel, Powerpoint. Most people believe that you have to be a rocket scientist to build a computer. You Don't! It is very easy. The first thing you will need to do, is get the parts. Motherboard, Processor, Video card, SOund card, DVD, CD-ROM, Monitor, RAM (SD-RAM) Case, speakers, DVD-EncoderCard, etc.. The next thing you will have to do, is set the jumpers on your motherboard, What this does, is set the amount of electricity that the motherboard will send to the CPU (processor). Different CPU's use different amounts of voltage. The newer CPU's use even less voltage.