Importance Program Of Computer In Today Era

 Introduction to Computer

In basic terms, a computer is an electronic device that processes data, converting it into information that is useful to people. Any computer-regardless of its type-is controlled by programmed instructions, which give the machine a purpose and tell it what to do. The computers discussed in this block -and which are everywhere around you are digital computers. As you will learn in , "Processing Data" digital computers are so called because they work "by the numbers".

That is, they break all types of information into tiny units, and use numbers to represent those pieces of information. Digital computers also work in very strict sequences of steps, processing each unit of information individually, according to the highly organized instructions they must follow. A lesser-known type of computer is the analog computer, which works in a very different way from digital computers. The earliest computers were analog systems, and today's digital systems owe a great deal to their analog ancestors. Analog and digital computers differ in many respects, but the most important distinction is the way they represent data.

Digital systems represent data as having one distinct value or another, with no other possibilities, Analog systems, however, rep- resent data as variable points along a continuous spectrum of values. This makes analog computers somewhat more flexible than digital ones, but not necessarily more precise or reliable. Early analog computers were mechanical devices, weighing several tons and using motors and gears to perform calculations. A more manageable type of a along computer is the old-fashioned slide rule. Computers can be categorized in several ways. 

For example, some computers are designed for use by one person, some are meant to be used by groups of people, and some are not used by people at all. They also can be categorized by their power, which means the speed at which they operate and the types of tasks they can handle. Within a single category, computers may be subcategorized by price, the types of hardware they contain, the kinds of software they can run, and so on.

Computers in Our World

Consider this sentence: "Computers are everywhere." 

• Does it sound like an overstatement?
• A cliché?

No matter how you perceive the impact of computers, the statement is true. Computers are everywhere. In fact, you can find them in some pretty unlikely places, including your family car, your home appliances, and even your alarm clock! In the past two decades, computers have reshaped our lives at home, work, and school. The vast majority of businesses now use computerized equipment in some way, and most companies are networked both internally and externally. More than half of all homes in the United States have at least one computer, and most of them are connected to the Internet. Workers who once had little use for technology now interact with computers almost every minute of the workday.

This lesson examines the many types of computers that are in common use today. Although this class will focus on personal computers (the ones that seem to sit on every desktop), you will first learn about the wide variety of computers that people use, and the reasons they use them. As your knowledge of computers grows, you will understand that all computers-regardless of their size or purpose-are basically similar. That is, they all operate on the same fundamental principles, are made from the same basic components, and need instructions to make them run.

History of Computers

How did computers come into existence? The history of computers is quite interesting. Imagine that you have a job where you have to perform nothing but calculations every day-at one point of time you will get bored. You might even become careless and start making mistakes. This is the reason inventors came up with something that would automate the task of performing calculations.

The Chinese abacus was one of the early inventions that helped humans per form mathematical calculations. After the invention of a multitude of diverse de vices such as the Jacquard loom (1805) and Charles Babbage's "analytical engine" (1834), calculating machines evolved into the modern computers that we see today. In the initial days, when electronic computing devices first came into use, there was much difference of opinion on the relative merits of analog computers over digital computers.

In fact, even by the end of the 1960s, only analog compute's were used for solving systems having finite difference equations. As more tum passed users realized that digital computing devices had the economics, power and scalability which were needed for dealing with large-scale computations. Starting from simple hand had calculators to supercomputers, today's world is dominated by digital computers.

Generations of Computers

Computers, at various stages of their evolution, have been divided into six generations. Every new generation has certain dramatic improvements when com- pared to its previous generations.

These improvements were the result of the technology used for building the computers, programming languages used and the computer system's internal organization. The six generations of computers are

• The Mechanical Era (1623-1900)
• First Generation Electronic Computers (1937-1953)
• Second-Generation (1954-1962)
• Third-Generation (1963-1972)
• Fourth-Generation (1972-1984)
• Fifth Generation (1984-1990)
• Sixth Generation (1990-till date)

The Mechanical Era (1623-1900)

Some of the important inventions during this era were the telescope, the earliest human-powered submarine, steam turbine, micrometer, pendulum clock, barometer, pressure cooker, thermometer, power loom, electromagnet, typewriter, and Morse code.

Machine/Device	year	Information
Adacus	3000 BS	A mechanical aid which can be used for easy counting is the abacus. Using a standard abacus, we can perform addition, subtraction, division and multiplication. Apart from this, we can also make use of the abacus for extracting square roots and cubic roots. The user has to memorize certain rules and move the beads around in the abacus for performing the above-mentioned arithmetic operations.
Napier’s bones	17th century	Napier's bones was invented by John Napier, a Scottish mathematician who was also known for inventing logarithms. The logarithm is one of the most famous tools which brought about a revolution in calculation methods by changing large and difficult multiplication operations to simple addition of entries in a table.
Pascaline	17th century	Pascaline was invented by Blaise Pascal, a French mathematician and philosopher. Pascaline had a series of wheels with teeth which could be turned using hands and it was used to handle numbers up to 999,999.999. Another name for Pascaline was numerical wheel calculator. It was one of the world's first mechanical adding machine.
Difference Engine and Analytical Engine	1823 and 1890	Charles Babbage, a computer pioneer, designed two classes of engines, the Difference Engine and Analytical Engine. In 1823, Babbage started the fabrication of a difference engine. It was so called because of the mathematical principle on which it was based, namely, the method of finite differences. In 1833, he began the construction of the Analytical Engine which was much more than a calculator. This helped in performing fully fledged general-purpose computation instead of mechanical arithmetic calculation.
Punched Cards	1890	Herman Hollerith, an American inventor, developed devices that were able to read information which had been punched into the cards automatically.

First-Generation Electronic Computers (1937-1953)

Some of the popular inventions of this time were the electron microscope, photo- copier, jet engine, helicopter, atomic bomb, microwave oven, and optic fiber, to name a few.

Machine/Device	year	Information
Atanasoff-Berry Computer	1942	Professor John Vincent Attunes off and his graduate student Cliff Berry designed and built the Atanasoff-Berry Computer (ABC) during 1939-1942. The ABC never functioned fully but had the credit of a patent dispute which was related to the invention of the computer.
Havard Mark-I	1944	Harvard Mark-1 was conceived by Howard Aiken, a professor in Harvard. It was designed and built by IBM. It was a relay-based calculator which was as big as a room with a fifty- feet long camshaft. This camshaft was used to synchronize thousands of component parts of the machine. It was used to create mathematical tables.
ENIAC	1946	ENIAC (Electronic Numerator Integrator and Calculator) was developed by John Mauchly and J Prosper Eckert. It was the first large, general-purpose computer to be made operational. It worked on vacuum tubes.
EDVAC	1949	EDVAC (Electronic Discrete Variable Automatic Computer) depicted a major improvement when compared to ENIAC. Mauchly and Eckert started working on EDVAC with the idea of having a program for a computer which was also stored inside the computer itself. This was made possible as EDVAC had more internal memory than any other computing device till date. In EDVAC, binary numbers were used instead of decimal numbers which made the construction of arithmetic units simple.

Second-Generation Computers (1954-1962)

In this era, some of the popular inventions were audio cassette, microchips, halo- gen lamp, and video disk.

Machine/Device	year	Information
TRADIC	1955	TRADIC (Transistor Digital Computer) was the first fully transistorized computer which made use of only transistors and diodes and no vacuum tubes. Bell Labs built it for the US Air Force, who needed this type of a lightweight computer for using in the air. There were nearly 800 transistors used instead of vacuum tubes. Transistors, highly efficient amplifying devices helped the machine to operate on less than 100 watts. This was 1/20th the power which was required for operating vacuum tube computers.
IBM 704	1954	IBM 704 was one of the first computers that were commercially available for the incorporation of floating point arithmetic’s and indexing. Another important feature of the 704 was its magnetic core memory which was more reliable than the cathode-ray-tube memory of its predecessor. IBM 704 was successful commercially as 123 704's were produced between 1955 and 1960.
TX-O	1956	The first programmable, general-purpose computer which was built by researchers in MIT was TX-0. The designers placed every transistor circuit inside a bottle for replacing it easily. This idea was conceived from vacuum.
LARC	1960	LARC (Livermore Atomic Research Computer) was supposedly one of the first supercomputers. The UNIVAC division of the Sperry Rand Corporation built it. The processing units in LARE made use of transistor circuitry as a result of which it was considered to be a second generation computer. It had many unique features. LARC was the fastest and also the last computer which was designed using decimal architecture, whereas almost all the computers in use today are based on binary architecture. It was the first computer which used two distinct processing units.
IBM 7030	1961	IBM 7030 computers, also known as Stretch, had the capability of multiprogramming, flexibility in the input and output, good memory capacity and also unrivalled speed. Solving large technical problems became fast and efficient by using these solid-state systems. They are generally designed in such a way that they are flexible in handling data of variable length with a high-speed performance and also enable commercial data processing by making use of decimal arithmetic.

Third-Generation Computers (1963-1971)

Some of the popular inventions of this time were calculator, computer mouse, RAM, Arpanet, ATM, Barcode reader, the daisy-wheel printer, floppy disk, the dot-matrix printer, liquid-crystal display, microprocessor, etc.

Machine/Device	year	Information
SYSTEM/360	1964	System/360 was announced by IBM in the year 1964. It was a family of 40 peripherals and six mutually compatible computers which had the capacity to work together. The System/360 was released at a stage when the company was shifting from using discrete transistors to integrated circuits and the company's major revenue came from electronic computer systems rather than punched cards which were used previously.
PDP-8	1965	The first minicomputer which was commercially successful was PDP-8, introduced by Digital Equipment Corp. It was sold for $18,000 which was one-fifth of the price of IBM's small 360 mainframe. The compactness, speed and cost efficiency was the reason for the PDP-8 to be used by small businesses, scientific laboratories and thousands of manufacturing plants.
CDC 7600	1969	The CDC 7600 came with a small core memory of 65,536 60-bit words which had a clock speed of 27 nanoseconds. It was five times the speed of CDC 6600. This is considered to be the last time when there was such a drastic increase in the speed, achieved from a single processor. The FORTRAN 70 compilers were supported by the 7600.
INTEL 4004	1971	Intel 4004 was one of the world's first microprocessors with a single chip introduced by Intel, invented by its own engineers Ted Hoff, Stan Mazar and Federico Fagin. The integrated circuit was taken one step ahead by using different parts which brought about the thinking capacity of a computer (using memory, CPU, input and output controls) on a single small chip.
INTEL 8008	1972	Intel's 8008 microprocessor marked a major improvement when compared to 4004, its predecessor. The eight-bit words used in it could afford 256 arrangements which were unique and used only zeros and ones. This was the first microprocessor which had the capability of holding letters of both upper and lower cases, 10 numerals and symbols with punctuation marks also.

Fourth-Generation Computers (1972-1984)

Some of the popular inventions of this time were the word processor, video game, Ethernet, laser printer, inkjet printer, VisiCalc spreadsheet, cell phones, Walk- man, MS-DOS, etc.

Machine/Device	Year	Information
ALTD	1974	Alto was designed by the researchers at the Xerox Palo Alto Research Centre and was considered to be the first workstation which had a built-in mouse used for input. Several files were stored simultaneously using Alto. It had the capability of linking to a local area network and also had various menu and icon features.
APPLE I	1097	which was designed by Steve. The Apple I board had two upper rows for a video terminal and two lower rows for the computer. The 6502 microprocessor in the white package is on the lower right.
VAX 11/78	1978	Digital Equipment Corporation designed the VAX 11/780. It was capable of addressing a maximum of 4.3 gigabytes of virtual memory which was a hundred times more than that of the capacity of minicomputers.
IBL PC	1981	The PC was introduced by IBM which ignited the personal computer market by increasing its growth. The first PC used Microsoft's MS DOS operating system which ran on 4.77 MHz Intel 8088 microprocessor.
LISA	1983	Apple introduced Lisa, the first personal computer which had a graphical user interface. Lisa ran on Motorola 68000 microprocessor and had a 1 megabyte RAM, dual 5 1/4-inch floppy disk drives, 5-megabyte hard drive and a 12-inch black-and-white monitor.
MACINOSH	1984	Macintosh was launched by Apple Computers which was the first successful computer to be mouse- driven along with a graphic user interface. Macintosh had many features of Lisa. The various applications which came along with the package are MacBain which needed the mouse and MacWrite used for word processing and demonstrates WYSIWYG (What You See Is What You Get).

Fifth-Generation Computers (1983-1990)

Some of the popular inventions of this era were CD-ROM, Windows programs, Doppler radar, high-definition television, first 3-D video game, etc.

Machine/Device	Year	Information
IBM-PC-AT	1984	PC-AT was released by IBM. It was several times faster than the original PC and based on the Intel 80286 chip and thus, was able to claim success with its remarkable increase in performance and storage capacity. It also included more RAM and accommodated high- density 1.2-megabyte 5 1/4-inch floppy disks.
PC/RT	1986	PC/RT and R2000-based systems were released by IBM and MIPS. It was the first RISC (Reduced instruction set computers)-based system. The IBM PC-RT consisted of 1 megabyte of RAM, a 1.2-megabyte floppy disk drive and 40-megabyte hard drive. It performed 2 million instructions per second.
PS/2	1987	PS/2 machines were introduced by IBM. The video graphics array standard and the 3 1/2- inch floppy disk drive was a result of this. OS/2 was also introduced by IBM which was an operating system. In PS/2 there were two BIOS, one was ABIOS (Advanced BIOS) which resulted in the production of a new interface which was a protected mode and was also used by OS/2. The other was CBIOS (Compatible BIOS) which had compatibility between PS/2 and PC/AT/XT.
Inter 80486	1989	The 80486 microprocessor was introduced by Intel along with the 1860 RISC/coprocessor chip. Both had more than a million transistors. The features of the RISC microprocessor include a clock speed of 33 MHz, 32-bit integer arithmetic and logic unit and a 64-bit floating-point unit.
Video Tostes	1990	Newton introduced Video Toaster which was a production and a video editing system for computers in the Amiga line and had special software and custom hardware. It has many tools for character generation, image manipulation, video switching, chroma keying and animation.

Sixth-Generation Computer

Machine/Device	Year	Information
Power-Book	1991	PowerBook was introduced by Apple. Motorola 68K CPUs were used in the first PowerBooks which were subsequently changed to PowerPC chips in the year 1995. Apple introduced silver PowerBook in the year 2001 which came in a titanium case, followed by anodized aluminum cases, thereby maintaining the Apple's new look.
Pentium Microprocessor	1993	In 1993, the first Pentium microprocessor was released. In the Intel's line of microprocessors, the Pentium was the fifth generation of the 'x86', which was the base for the IBM PC and its clones. Several advances were introduced by Pentium which resulted in faster running programs having the ability of executing many instructions at the same time and also support music and graphics.
Sun ultra Workstation	1996	The Sun Ultra workstation was introduced by Sun Microsystems in the year 1996. It was a processor-based workstation having a 64-bit Opteron with a best-in-class performance which led to faster project development and increased productivity. Sun Ultra workstation could run various OS like Microsoft Windows, Linux, Solaris Operating System on a single x64-based system.
iMac	1998	Apple Computers released the colorful iMac, an all-in-one system. It has a speed of up to 2.4GHz, Intel Core 2 Duo, 1GB memory, 250GB hard drive1, 8x double-layer SuperDrive ATI Radeon HD 2400 XT with 128MB memory. The iMac uses only USB connections and it includes a floppy disk drive.
Apple iMac Pedestal Computer	2002	The CRT-based iMac computer was re-designed by Apple using an LCD screen with a flat panel which was mounted on a pedestal having a chrome arm, enabling the display to be rotated in many ways as per requirement. The pedestal which is the actual computer consists of a G4 processor which runs at a speed of 700 MHz at its low-end configuration. In the high-end model, there is an Apple SuperDrive which had the capability of handling both CD-RW discs and DVD-R.
Power Mac G5	2003	The Power Mac G5 was introduced by Apple as a professional-grade computer. It was one of the most powerful computers introduced in Apple's line-up. It was widely known to be the first 64-bit PC and was claimed by Apple to be the fastest personal computer ever built. Power Mac G5 came in three different models which shared the same physical case but differed in their performance and certain features. The 1.6 Gizmodo had an 80 GB hard drive and 256 megabytes of RAM and also had the capability of employing 4 GB of RAM to the maximum. The 1.8 and dual-processor 2.0 GHz models had 512 MB of RAM and a capability of employing 8 gigabytes of RAM to the maximum. An ATI Radeon 9600 graphics card was also a part of the dual-processor model.

Individual Users to Computer

Most computers are meant to be used by only one person at a time. Such computers are often shared by several people (such as those in your school's computer lab), but only one user can work with the machine at any given moment .

Best Computer Programming Language.

The six primary types of computers in this category are

1. Desktop computers
2. Workstations
3. Notebook computers
4. Tablet computers
5. Handheld computers
6. Smart phones

These systems are all examples of personal computers (PCs)-a term that refers to any computer system that is designed for use by a single person. Personal computers are also called microcomputers, because they are among the smallest computers created for people to use. Note, however, that the term personal computer or PC is most often used to describe desktop computers, which you will learn about in the following section.

Although personal computers are used by individuals, they also can be connected together to create networks. In fact, networking has become one of the most important jobs of personal computers, and even tiny handheld computers can now be connected to networks. You will learn about computer networks in Chapter 7, "Networks."

Desktop Computers

The most common type of personal computer is the desktop computer-a PC that is de- signed to sit on (or under) a desk or table. These are the systems you see all around you, in schools, homes, and offices, and they are the main focus of this book.

Today's desktop computers are far more powerful than those of just a few years ago, and are used for an amazing array of tasks. Not only do these machines enable people to do their jobs with greater ease and efficiency, but they can be used to communicate, produce music, edit photographs and videos, play sophisticated games, and much more. Used by everyone from preschoolers to nuclear physicists, desktop computers are indispensable for learning, work, and play.

As its name implies, a desktop computer is a full-size computer that is too big to be carried around. The main component of a desktop PC is the system unit, which is the case that houses the computer's critical parts, such as its processing and storage de- vices.

There are two common designs for desktop computers. The more traditional desktop model features a horizon- tally oriented system unit, which usually lies flat on the top of the user's desk. Many users place their monitor on top of the system unit . Vertically oriented tower models have become the more popular style of desktop system. This design allows the user to place the system unit next to or under the desk, if desired.

Computer Workstations

A workstation is a specialized, single-user computer that typically has more power and features than, a standard desktop PC. These machines are popular among scientists, engineers, and animators. who need a system with greater- than-average speed and the power to perform sophisticated tasks. Workstations often have large, high-resolution monitors and accelerated graphics- handling capabilities, making them suitable for advanced architectural or engineering design, modeling, animation, and video editing.

Notebook Computers

Notebook computers, as their name implies, approximate the shape of an 8.5-by-11-inch note book and easily fit inside a brief- case. Because people frequently set these devices on their lap, they are also called laptop computers. Notebook computers can operate on alternating current or special batteries. These amazing devices generally weigh less than eight pounds, and some even weigh less than three pounds! During use, the computer's lid is raised to reveal a thin monitor and a keyboard. When not in n use, the device folds up for easy storage.

Note- books are fully functional microcomputers, the people who use them need the power of a full-size desktop computer wherever they go. Because of their portability, notebook PCs fall into a category of devices called mobile computers-systems small enough to be carried by their user. 

Some notebook systems are designed to be plugged into a docking station, which may include a large monitor, a full-size keyboard and mouse, or other devices. Docking stations also pro- vide additional ports that enable the note- book computer to be connected to different devices or a network in the same manner as a desktop system.

Tablet PCs 

The tablet PC is the newest development in portable, full-featured computers. Tablet PCs offer all the functionality of a notebook PC, but they are lighter and can accept input from a special pen-called a stylus or a digital pen-that is used to tap or write directly on the screen.

Many tablet PCs also have a built-in microphone and special soft- ware that accepts input from the user's voice. A few models even have a fold-out keyboard, so they can be transformed into a standard notebook PC. Tablet PCs run specialized versions of standard programs and can be connected to a network. Some models also can be connected to a keyboard and a full-size monitor.

Handheld PCs

Handheld personal computers are computing devices small enough to fit in your hand. A popular type of handheld computer is the personal digital assistant (PDA). A PDA is no larger than a small appointment book and is normally used for special applications, such as taking notes, displaying telephone numbers and addresses, and keeping track of dates or agendas. Many PDAs can be connected to larger computers to exchange data.

Most PDAs come with a pen that lets the user write on the screen. Some handheld computers feature tiny built-in key- boards or microphones that allow voice input. Many PDAs let the user access the Internet through a wireless connection, and several models offer features such as cellular telephones, cameras, music players, and global positioning systems.

Smart Phones

Some cellular phones double as miniature PCs. Because these phones offer advanced features not typically found in cellular phones, they are sometimes called smart phones. These features can include Web and e-mail access, special software such as personal organizers, or special hardware such as digital cameras or music players. Some models even break in half to reveal a miniature keyboard.

Computers for Organizations

Some computers handle the needs of many users at the same time. These powerful systems are most often used by organizations, such as businesses or schools, and are commonly found at the heart of the organization's network. Generally, each user interacts with the com putter through his or her own device, freeing people from having to wait their turn at a single keyboard and monitor.

The largest organizational computers support thousands of individual users at the same time, from thousands of miles away. While some of these large-scale systems are devoted to a special purpose, enabling users to perform only a few specific tasks, many organizational computers are general-purpose systems that support a wide variety of tasks.

Network Servers

Today, most organizations' networks are based on personal computers. Individual users have their own desktop computers, which are connected to one or more centralized computers, called network servers. A network server is usually a powerful personal computer with special software and equipment that enable it to work. function as the primary computer in the net work.

PC-based networks and servers offer companies a great deal of flexibility. For example, large organizations may have dozens or hundreds of individual servers working together at the heart of their network. 

When set up in such groups some times called clusters or server farms network servers may not even resemble standard PCs. For example, they may be mounted in large racks or reduced to small units called "blades," which can be slid in and out of a case. In these large networks, different groups of servers may have different purposes, such as supporting a certain set of users, handling printing tasks, enabling Internet communicate nans, and so on.

A PC-based server gives users flexibility to do different kinds of tasks. This is because PCs are general-purpose machines, designed to be used in many ways For example, some users may rely on the server for e-mail access, some may use it to perform accounting tasks, and others may use it to perform word processing or database management jobs. The server can support these processes, and many others, while storing information and programs for many people to use.

Depending on how the net work is set up, users may be able to access the server in multiple ways. Of course, most users have a standard desktop PC on their desk that is permanently connected to the network. Mobile users, however, may be able to con nest a notebook PC or a hand- held device to the network by wireless means. When they are away from the office, users may be able to use the Internet as a means of connecting to the company's network servers.

Mainframe Computers

Mainframe computers are used in large organizations such as insurance companies and banks, where many people frequently need to use the same data. In a traditional mainframe environment, each user accesses the mainframe's resources through a device called a terminal. There are two kinds of terminals. A dumb terminal does not process or store data, it is simply an input/ output (I/O) device that functions as a window into a computer located somewhere else. An intelligent terminal can perform some processing operations, but it usually does not have any storage. In some mainframe environments, how- ever, workers can use a standard personal computer to access the mainframe.

Mainframes are large, powerful systems. The largest mainframes can handle the processing needs of thousands of users at any given moment. But what these systems offer in power, they lack in flexibility. Most mainframe systems are designed to handle only a specific set of tasks. In your state's Department of Motor Vehicles, for example, a mainframe system is probably devoted to storing information about drivers, vehicles, and driver's licenses, but little or nothing else. By limiting the number of tasks the system must perform, administrators preserve as much power as possible for required operations.

You may have interacted with a mainframe system without even knowing it. For example, if you have ever visited an airline's. Web site to reserve a seat on a flight, you probably conducted a transaction with a mainframe computer.

Minicomputers

First released in the 1960s, minicomputers got their name because of their small size compared to other computers of the day. The capabilities of a minicomputer are somewhere between those of mainframes and personal computers. For this reason, minicomputers are often called midrange computers.

Like mainframes, minicomputers can handle much more input and output than personal computers can. Although some "minis" are designed for a single user, the most powerful minicomputers can serve the input and output needs of hundreds of users at a time. Users can access a central minicomputer through a terminal or a standard PC

Supercomputers

Supercomputers are the most powerful computers made, and physically they are some of the largest . These systems can process huge amounts of data, and the fastest supercomputers can perform more than one trillion calculations per second. Some supercomputers can house thousands of processors. Supercomputers are ideal for handling large and highly complex problems that require extreme calculating power. For example, supercomputers have long been used in the mapping of the human genome, forecasting weather, and modeling complex processes like nuclear fission.

Computers in Society

• How important are computers to our society? 

People often talk in fantastic terms about computers and their impact on our lives. You probably have heard or read expressions such as "computers have changed our world" or "computers have changed the way we do everything" many times. Such statements may strike you as exaggerations, and sometimes they are. But if you stop and really think about the effect computers have had on our daily lives, you still may be astonished.

One way to gauge the impact of computers is to consider the impact of other inventions. Can you imagine, for instance, the many ways in which American life changed after the introduction of the automobile? Consider a few examples:

• Because of the car, people were able to travel farther and cheaper than ever before, and this created budge opportunities for businesses to meet the needs of the traveling public
• Because vehicles could be mass-produced, the nature of manufacturing and industry changed and throngs of people began working on assembly lines.
• Because of road development, suburbs became a feasible way for people to live close to a city without actually living in one
• Because of car travel, motels, restaurants, and shopping centers sprang up in places where there had previously been nothing.

Think of other great inventions and discoveries, such as electricity, the tele- phone, or the airplane. Each, in its own way, brought significant changes to the world, and to the ways people lived and spent their time. Today, still relatively soon after its creation, the computer is only beginning to make its mark on society.

Why Are Computers So Important?

People can list countless reasons for the importance of computers. For someone with a disability, for example, a computer may offer freedom to communicate, learn, or work without leaving home. For a sales professional, a PC may mean the ability to communicate whenever necessary, to track leads, and to manage an ever-changing schedule. For a researcher, a computer may be the workhorse that does painstaking and time-consuming calculations.

But if you took all the benefits that people derive from computers, mixed them together, and distilled them down into a single element, what would you have? The answer is simple: information. If you work in one place and need to perform various tasks, a desktop computer is the best choice. Choose a desktop computer if you want to

1. Work with Graphics-Intensive or Desktop Publishing Applications. Complex graphics and page-layout pro- grams require a great deal of system resources, and a desktop system's large monitor reduces eye fatigue.
2. Design or Use Multimedia Products. Even though many portable computers have multimedia features, you can get the most for your money with a desktop system. Large screens make multimedia programs easier to see, and stereo-style speakers optimize sound quality.
3. Set Up Complex Hardware Configurations. A desktop computer can support multiple peripherals-including printers, sound and video sources, and various external devices at the same time. If you want to swap compo nets, or perform other configuration task, a desktop system will provide many option.

Computers are important because information is so essential to our lives. And information is more than the stuff you see and hear on television. Facts in a text- book or an encyclopedia are information, but only one kind. Mathematical for mules and their results are information, too, as are the plans for a building or the recipe for a cake. Pictures, songs, addresses, games, menus, shopping lists, resumes the list goes on and on.

All these things and many others can be thought of as information, and they can all be stored and processed by computers. (Actually, computers store these things as data, not as information, but you'll learn the difference between the two later in this book.) So, when you consider the importance of computers in our society, think instead about the importance of information. As tools for working with information, and for creating new information, computers may be one of humanity's most important creations.

Using of Computer in Today Era

• Home
• Education
• Small Business
• Industry
• Government
• Health Care
• Banking
• Communication
• Police Department
• Retail

01: Computer use at Home

In many American homes, the family computer is nearly as important as the refrigerator or the washing machine. People cannot imagine living without it. In fact, a growing number of families have multiple PCs in their homes; in most cases, at least one of those computers has an Internet connection. 

Why do home users need their computers?

Communications:

Electronic mail (e-mail) continues to be the most popular use for home computers, because it allows family members to communicate with one another, and to stay in contact with friends and coworkers.

Business Work Done at Home:

Thanks to computers and Internet connections, more people are working from home than ever before. It is possible for many users to connect to their employer's network from home and do work that could not be done during regular business hours. Computers also are making it easier for people to start their own home-based businesses.

Schoolwork: 

Today's students are increasingly reliant on computers, and not just as a replacement for typewriters. The Internet is replacing printed books as a reference tool, and easy-to-use software makes it possible for even young users to create polished documents.

Entertainment:

If you have ever played a computer game, you know how enjoyable they can be. For this reason, the computer has replaced the television as the entertainment medium of choice for many people. As computer, audio, video, and broadcast technologies converge, the computer wile someday be an essential component of any home entertainment center.

Finances: 

Computers and personal finance software can make balancing your checkbook an enjoyable experience. Well, almost. At any rate, they certainly make it easier, and home users rely on their PCs for bill paying, shopping, investing, and other financial chores.

02: Computer use in Education

More and more schools are adding computer technology to their curricula, not only teaching pure computer skills, but incorporating those skills into other classes. Students may be required to use a drawing program, for example, to draw a plan of the Alamo for a history class, or use spreadsheet software to analyze voter turnouts during the last century's presidential elections.

Educators see computer technology as an essential learning requirement for all students, starting as early as preschool. Even now basic computing skills such as keyboarding are being taught in elementary school classes see. In the near future, high school graduates will enter college not only with a general diploma, but with a certification that proves their skills in some area of computing, such as networking or programming.

03: Computer use in Small Business

Many of today's successful small companies simply could not exist without computer technology. Each year, hundreds of thousands of individuals launch businesses based from their homes or in small- office locations. They rely on inexpensive computers and software not only to perform basic work functions, but to manage and grow their companies.

These tools enable business owners to handle tasks-such as daily accounting chores, inventory management, marketing, payroll, and many others-that once required the hiring of outside specialist. As a result, small businesses become more self-sufficient and reduce their operating expenses.

04: Computer use in Industry

Today, enterprises use different kinds of computers in many combinations. A corporate headquarters may have a standard PC-based network, for example, but its production facilities may use computer-controlled robotics to manufacture products.

Here are just a few ways computers are applied to industry:

Design:

Nearly any company that designs and makes products can use a computer-aided design or computer-aided manufacturing system in their creation.

Shipping:

Freight companies need computers to manage the thousands of ships, planes, trains, and trucks that are moving goods at any given moment. In addition to tracking vehicle locations and contents, computers can manage maintenance, driver schedules, invoices and billing, and many other activities.

Process Control:

Modern assembly lines can be massive, complex systems, and a breakdown at one point can cause chaos throughout a company. Sophisticated process-control systems can oversee output, check the speed at which a machine runs, manage conveyance systems, and look at parts inventories, with very little human interaction.

05: Computer use in Government

Not only are governments big consumers of technology, but they help to develop it as well. As you will learn in Chapter 8, "Presenting the Internet," the U.S. government played a key role in developing the Internet. Similarly, NASA has been involved in the development of computer technologies of all sorts. 

Today, computers play a crucial part in nearly every government agency:

Population:

The U.S. Census Bureau was one of the first organizations to use computer technology, recruiting mechanical computers known as "difference engines" to assist in tallying the American population in the early 20th century.

Taxes: 

Can you imagine trying to calculate Americans' tax bills without the help of computers? Neither could the Internal Revenue Service. In fact, the IRS now encourages taxpayers to file their tax returns online, via the Internet.

Military: 

Some of the world's most sophisticated computer technology has been developed primarily for use by the military. In fact, some of the earliest digital computers were created for such purposes as calculating the trajectory of missiles. To day, from payroll management to weapons control, the armed forces use the widest array of computer hardware and software imaginable.

Police:

When it comes to stocking their crime-fighting arsenals, many police forces consider computers to be just as important as guns and ammunition. Today's police cruisers are equipped with laptop computers and wireless Internet connections that enable officers to search for information on criminals, crime scenes, procedures, and other kinds of information.

06: Computer use in Health Care

Pay a visit to your family doctor or the local hospital, and you'll find yourself surrounded by computerized equipment of all kinds. Computers, in fact, are making health care more efficient and accurate while helping providers bring down costs. Many different health care procedures now involve computers, from ultrasound and magnetic resonance imaging, to laser eye surgery and fetal mentoring.
Surgeons now can use robotic surgical devices to perform delicate operations, and even to conduct surgeries remotely. New virtual-reality technologies are being used to train new surgeons in cutting-edge techniques, without cutting an actual patient.

But not all medical computers are so high-tech. Clinics and hospitals use standard computers to manage schedules, maintain patient records, and perform billings. Many transactions between physicians, insurance companies, and pharmacies are conducted by computers, saving health care workers time to devote to more important tasks. E-Health is the term used for healthcare practice that is supported by electronic processes and communication.

Another database system used in many hospitals is the appointment system. These systems allow the patient to check the appointment time with his/her consultant. These systems also allow the patient or consultant to cancel or re-schedule their appointments online. Computers control diagnostic machinery in hospitals. A computer analyses the data from diagnostic machinery and diagnoses the problem, for instance, the images from the MRI scan are unintelligible until they have been processed by a computer.

The information available on uncommon illnesses in expert systems is useful to doctors. Junior doctors can make use material stored in CDs for learning new information.

07: Computer use in Banking

Today, banks cannot exist without computer technology. In the past, banks were open only for a fixed time from 9 am to 3pm and all the information on bank accounts, and the past, banks were open and stored in ledgers and ac count books. In order to draw money, customers had to wait for the tank to open that they could to draw cash and then pay for their purchases.

Nowadays, the whole scenario of banking has changed. With the development of Internet banking, you can open your account; check your balances online, move money, pay bills and print statements from the comfort of your home. Banks use computers extensively to operate efficiently.

Bankers' Automated Clearing Services (BACS) Various financial transactions between banks are carried out by the BACS through computers. These transactions include chequeen clearance, payment of salary and standing orders or direct debits payment. All the previous days' transactions are processed simultaneously by the BACS by using batch processing. All these data, after being processed, is passed among the banks through magnetic tapes. All these transactions maintain a log. 

Online Banking Online banking (or Internet banking) allows you to connect to your bank using a computer via Internet. You can then view your accounts, transfer money between accounts, print copies of checks, statements and pay bills online. Online banking allows customers to do their banking twenty-four hours a day and seven days a week. Online bank sites generally execute and confirm transactions faster than traditional banking methods. However, with online banking, you cannot deposit money and security on the accounts has to be rigorous lest they be hacked by unauthorized persons and fraudsters.

Automated Teller Machines (ATM) An ATM can be defined as a banking terminal used to make transactions without a human teller. It is used to draw cash from your bank account. You insert the ATM card into the ATM machine, type your PIN number and the amount you wish to withdraw. The cash comes out through the cash dispenser.

The ATM allows the customer to:

• Get cash
• Request a withdrawal statement
• Check account balance

Computer use in Communication

The way we communicate in today's world is largely influenced by computers. We can now chat with people any where on the globe. Messages can be sent and the sent messages are received by their respective destinations in fractions of seconds ins matter how many miles they are awe. Fuming goods from any part of the globe is also easy nowadays where the stove purchased online are delivered at your doorsteps. Making use of computers for the purpose of communication has made the world look smaller and the communities in which we live seem latera.

Electronic Mail:

The system used for transmuting messages Vereen computers which have an Internet connection is called Electronic mail, popularly known as amass. In today's world, e-mail is one of the most widespread and popular means of communication used by people using the Internet daily. The procedure used for sending an e-mail is to type the required information in the space provided along with the e-mail address of the recipients. 

This message is received by the recipient's mail server. The mailbox of the recipient stores this message till the time the recipient downloads it onto his computer. We can also send computer files and text messages as attachments along with the message. Thus, this facility enables us to send and receive documents and scanned pictures through e-mails. All the e mails that we receive can be read or saved or even deleted based on our requirement. E-mail communication has many advantages like cost efficiency, speed, flexibility, and efficient transferring of files. Apart from these advantages, this can also lead to various disadvantages like spam, viruses, etc. 

Audio and Video Conferencing:

Audio conferencing allows people in different locations to talk to each other as a group. This is also known as Teleconferencing it is a real-time con Mimi cation system where people can chat with each other. Each person has a user ID number. If he wants to log on to the conference call, he has to switch on his conference call device and enter his user ID number. An automated voice informs the room about the entry of a new person. Others greet hum and they continue with their conversation. 

The main advantage of audio conferencing is that it saves travelling time and travelling cost. Routine business meetings can be held between distant offices. But it is sometimes difficult to exchange ideas when people cannot see each other face to face. Video conferencing is similar to audio conferencing except that people in the meeting can now see one another by using video cameras. Video cameras send live images over telephone lines. By using video cameras, people can see the other members in the group as well as hear them. Not many people can have video conferencing systems because the hardware and software needed to set up a videoconferencing system can be very expensive.

News Groups: 

News Groups provide an area online for discussion. People can discuss news items and state their opinions. Anyone can post a message (article) to a newsgroup and usually, anyone can view the messages. How ever, the person has to sign in before posting a message. Each the message has a title. When people reply to the message, in grouped with the arable. This is known as thread. The trail of discussion can be followed on a specific thread. The main advantage of discussion groups are that you can get answers for a question you have posted, from other members. It is an excellent way of learning about a topic. The main drawback of these groups is that people can post abusive messages. On the other hand, there are some people who join these groups to cause aggravation, they are called trolls.

Instant Messaging (IM)

IM stands for Instant Messaging, that is, when a person types a message, the other person can see it mimed atelia in their IM window. It is a text based service and allows us to maintain a luth of people whom we often in terrace with using instant messaging. This list is called a contact last. When you are online, you will be able to send messages to your contacts who are also onia ne. When a message is sent, a small window opens up, where the con tact can see your message and also type in h her message.

The difference between e-mail and Instant Messaging is that the IM window shows the message as soon as it is typed. Instant Messaging has become a very powerful way of communicating as it allows you to chat in 'real time" with other people who also have an IM client. It c can also be done with videos. In Video IM, a web camera and a microphone with a headset is used. You can see, talk and listen at the same time.

Computer Police Department

Nowadays, criminals make use of the latest technology to commit their crimes. Therefore, the police have developed equally sophisticated methods of crime detection Computers are used to handle the vast amount of data and criminal intelligence information gathered every year, which is stored on a networked computer system called Police National Computer (PNC).

The PNC allows the Police to share information throughout the count making it easier for them to work together and piece the evidence to gathers. When a police officer makes an enquiry, he gets the information in seconds PNC has two main databases-one holds information on stolen vehicles and the other has details on individuals who have committed crimes. It is connected to another powerful computer running the Automated Fingerprint Ident deification system.

The science of making use of the pattern of ridges on a person's fingertips for the purpose of identification is called fingerprinting Fingerprints obtained from objects at the scene of a crone are photographed and scanned into a com punter terminal. These powerful pattern-matching computers make the task of finding a match much quicker-often within minutes.

Computers are also used in DNA profiling DNA is a substance that exists in almost every cell in the human body and each person has a slightly different variation of it. There is now a national database containing the DNA profiles of criminals. Just like the fingerprint index, as more records are added, it is a bit more likely for a crime to be solved with the help of this index. The system uses samples from mouth swabs or hair strands. A DNA profile is built up and the computer can then be used to make comparisons against known criminals.

Computer Retail

Computers are used in supermarkets for a range of purposes such as receiving, storing, retrieving, manipulating and sending data. In supermarkets, once you have picked up the goods, you go to the cashier to pay for the goods. The cashier swipes ranch item over a barcode reader. The computer reads the barcode, identifies the product, takes the price from the shop database and deducts the item from the shop stock. When the customers use debit or credit cards, they are swiped at the till. This process automatically transfers money to the supermarket's account from the customer's account. The cashier then gives an itemized bill to the customer. Computers are used in stock control as well.

The store manager has to keep a careful check on the amount of stock in a supermarket. The stock is controlled efficiently by maintaining a stock database in the central computer Once the item has been scanned, the barcode is passed to the stock database that is stored in the central com punter. Whenever the barcode of a product is scanned, the computer reduces the level of stock for that product by one. When stocks fall below the re order level, an order for more stock is automatically sent to the distribution warehouse The stock database gives accurate and up-to-date information of the current stock levels. An Electronic Funds Transfer Point of Sale (EFTPOS) terminal is a checkout connected to a computer, with a hark code scanner.

This helps in transferring money from a customer's account by making use of his credit or debit cards. In an EFTPOS, a magnetic card reader is present in the till. At the back of the credit or debit card, a black magnetic strip contains the electronic details. When the card is swiped through the magnetic reader on the till, the information is picked up by the reader and a request for approval is automatically sent to the bank computer via the telephone network. The bank computer checks whether there is enough money in the account to complete the purchase, checks its authenticity and then sends back a message to the EPOS to authorize the purchase. The funds are then transferred from the customer's account to the supermarket's account. Finally, the customer signs on the receipt printed by the reader.

Supermarkets have also introduced Internet shopping Nowadays, supermarkets have their own website and entourage their customers to visit their website to purchase the goods. This helps customers in selecting the products of their choice by browsing through the various web pages having the product information along with their pictures. As each item is selected, it goes one the Virtual Trolley The total cost of the selected goods is displayed. The payment for the goods is debit goes into the or debit cards. Once the payment is approved, the order is transmitted to the store where the goods are packed and sent to the customers.