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Faces of the Future: the Getty's L.A.Culture Net

The Internet is the road to the future. Governments, businesses and nonprofits are uploading information about their organizations onto the World Wide Web, and the public is conducting more and more of its activities on-line. Due to the digital revolution people can obtain information about art and culture in the net. Today, many museums realize that developing a Web site is not just an option, but a necessity. Los Angeles Culture Net (LACN) links art and cultural information from several Los Angeles institutions at a network. The project uses information technology to create web-pages of cultural resources. Though Philadelphia and Cleveland, have developed on-line city networks, LACN is one of the first focused on cultural heritage. The organizers are trying to encourage cultural organizations to participate actively. "Faces of L.A." links digital archives and collections from several institutions in a virtual database that provides instant access to a wide variety of resources and make them searchable. To find all Leonardo da Vinci's masterpieces one has to travel to several countries, but using a virtual database you can see the drawings or paintings, no matter where they*re located, and compare and contrast them. "Faces of L.A." project comprises five museums, three libraries and the American Film Institute, The California Museum of Science and Industry site describes its "Snap Shot Science" project, which links Los Angeles artists and scientists with middle school students. The students use the "Faces of L.A." database as both a research tool and a resource for exhibition material.

Actually, some museum directors get very concerned about intellectual property rights, but they really feel the further necessity to combine their efforts to develop more curriculum units and add more institutions to L. A. Culture Net. They are also working with the California Arts Council to develop a statewide project called California Culture Net.

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Второй текст

The History of Computers

During the 17fh and the 18 centuries mathematicians devised many easy ways of calculating. But it was not until the early 1800s that the first calculating machine appeared and, not too long after, Charles Babbage designed a machine which became the basis for building today's computers.

An American named Vannevar Bush built the first analog computer in 1930. Military men used this device in the World War II to help aim guns. Prof. Howard Aiken and some people from IBM responsible for the invention of the first digital computer, named MARK I, completed it in 1944. This was the first machine that could figure out long lists of mathematical problems at a very fast rate. In. 1946 two engineers at the University of Pennsylvania, J.Eckert and J.Mauchly, built the first digital computer using parts called vacuum tubes. They named their new invention ENIAC. Another important advancement in computers came in 1947, when John von Newmarm developed the idea of keeping instructions for the computer inside the computer's memory. There were about 700 computers in the United States in 1955 and about 22,000 by 1964. Engineers of the Massachusetts Institute of Technology developed the first electronic computer. It contained 19,000 vacuum tubes, some of which burnt every few days. This computer completely filled a large room, and the cost of electricity to run it was enormous. Early computer memories required 10,000 to 20,000 watts of power, enough to run a small factory. Modeftj computers operate on 60 watts, about the same as a small light bulb. Since then, computers have gone through four generations: digital computers using vacuum tubes in the 1950s, transistors in the early 1960s, integrated circuits in the niid-60s and a single chip in the 1970s. With integrated circuits computers have truly come of age*. Engineers found that the only way to shorten calculation time was.simply to reduce the length of electric circuits that electrons had to travel. They did it by compressing and miniaturizing the circuits themselves, with a technique known as "large-scale integration" - LSI.

A chip is a square or rectangular piece of silicon, usually from 0.1 to 0.25 inch? upon which several layers of an integrated circuit are imprinted, after which the chip is encapsulated in plastic, ceramic or metal. Fourth-generation computers can complete approximately 1,000,000 instructions per second.

Due to the personal computing revolution, the military, and the advancement in related fields computers have shrunk from multi-ton mainframe monsters of vacuum tubes costing tens of thousands of dollars to ten pound desktops and two-ounce handhelds. The widespread availability of computers has changed the world forever. The microchip technology which made the personal computers possible has put chips not only into computers,, but also into domestic appliances. Scientists and engineers rely on computers for solutions to problems in almost every7 field of national economy.

*come of age - here: to achieve a new stage in its development

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Третий текст

Personal Computers

Warm-up: What is California famous for?

ЦЪаг firms producing personal computer do you know? Is a personal computer and wordprocessor one and the same thing? Can you name the fields of human activity where personal computers are vitally important?

In 1980 IBM decided that there was a market for 250,000 PCs, so they set up a special team to develop the first IBM PC. It went on sales in 1981 and set a world-wide standard for IBM-compatibility which, over the next ten years, was only seriously challenged by one other company, Apple Computers. Since then, over seventy million PCs made by IBM and other manufacturers have been sold. Over this period, PCs have become commodity items.

The history of the multi-billion-dollar PC industry .has 6een one of mistakes. Xerox Corporation funded the initial research on personal computers in their Palo Alto laboratory in California. However, the company-failed to capitalize on this work, and the ideas that they put together went into the operating system developed for Applets computers. This was a graphical interface: using a mouse, the user clicks on icons which represent the function to be performed. The engineers developed the first IBM PC using existing available electrical components. When IBM were looking for an operating system, they went Initially to Digital Research who were leaders in command-based operating systems(these are operating systems in which the users type in commands to perform a function). When the collaboration between IBM and Digital Research failed, IBM turned to Bill Gates, then 25 years old, to write their operating system. Bill Gates founded Microsoft on the basis of the development of MS/DOS, the initial operating system for the IBM PC. The original IBM PC had a minimum of 16K of memory, but this could be upgraded to 512 К if necessary, and ran with a processor speed of 4.77 MHz. Ten years later in 1991 IBM were making PCs with 16Mb of memory, expandable to 64 Mb, running with a processor speed of 33MHz. 

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Четвертый текст

An Artificial Tongue

Computers, Bill Gates is fond of pointing out, lack most of the basic senses that humans often take for granted. Some advanced machines can hear and speak - poorly - but most are blind and oblivious to touch, smell and temperature. Electronic devices may soon gain a sense of taste, however, thanks to tiny electromechanical machines so-called "smart tongues" invented at Pennsylvania State University by husband-and-wife engineers Varadan who presented their designs at a conference in San Diego. The Varadans predict that within a few years the devices will be cheap and sensitive enough to find myriad uses. Stuck inside milk cartoons and juice bottles, some sensors might enable checkout scanners to detect the unwanted bacteria. Slightly different versions could be mounted on aircraft wings to alert pilots when ice begins to form. There is good reason to believe that this is more than daydreams. Smart tongues are very small, made from simple materials - silicon, quartz, aluminum - using the same process by which the cheapest computer chips arc produced. A second benefit is that they arc wireless. Unlike most other micro machines, these sensors receive power from radio waves or microwaves. With no batteries and no tether to a computer they can be placed almost everywhere.

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Пятый текст количество символов в тексте: 3459

Once upon a Time

In the early 70s there was no such device as a personal computer. The most common type of computers were expensive mainframes housed in glass-enclosed cooled rooms ('glass houses') and used mostly by large organizations and corporations. These room-sized computers typically relied on large spools of magnetic tape and punch cards to process data. Few people had access to computers at this time, only elite groups of specialists were programming, operating and maintaining mainframes, All departments and workers in a company spent a lot of time negotiating with MIS (management information system) professionals if they wanted to write or change any program. The introduction of VisiCalc* on the Apple IP* in 1979 meant that accountants could compute their own numbers and not wait hours or longer while MIS specialists ran programs for them. Low-cost PCs also made it possible for people to have computers in their homes. And the PC revolution in the "80s laid the foundation for the Internet revolution of the '90s. Perhaps more than any other industry, the development of the personal computer business is a fascinating tale of companies that made millions of dollars while others went bankrupt and disappeared. By 1980, IBM had decided to build personal computers and needed a PC operating system. (Computers are born empty; they need operating systems to be presentable.) So IBM hired Microsoft to build its operating system. They released the PC on the market in August 1981. Microsoft's DOS was one of the three official PC operating systems (including Mackintosh from the Apple) but quickly beat the other two. DOS was primitive at a time when the computer was wearing UNIX from Bell Labs or some variant of the revolutionary window-menu-mouse system that Xerox had introduced in the 1970s. But despite (or maybe because of) its stodginess, DOS established itself as the school uniform of computing. It was homely but everyone needed it. Gates had brokered a marriage between other people's ideas and come up with a hit. DOS was even bigger than BASIC, Gates had it made. Another computer company, Apple, released the Mackintosh in January 1984: a sophisticated computer was now available to the masses. Henceforth DOS was not merely homely, it was obsolete. But it continued to rake the money. In May 1990, Microsoft finally perfected its own version of Apple windows and called it Microsoft Windows 3.0 - another huge hit. By the early '90s, electronic mail and the Internet had become big. Technologists forecast an Internet-centered view of computing called "mirror worlds" and "information superhighway". The World Wide Web emerged in 1994, making browsers necessary, and Netscape was founded that same year. Sun Microsystems developed Java, the Internet programming language. Gates hung back. It wasn't until 1996 that Microsoft finally, according to Gates himself, "embraced the Internet wholeheartedly". Microsoft's first browser. Internet Explorer 1.0, was licensed from a company called Spyglass. Today Microsoft is the world's most powerful supplier of Web Browsers. In 1995 Gates published a book (co-authored with Nathan Myhrvold) called "The Road Ahead". Peering far into the future, he glimpsed a technology-rich dreamworld where you will be able to "watch "Gone with the Wind" with your own face and voice replacing Vivien Leigh's or

Clark GablesApparently this is just what the public had been dying to do, for "The Road Ahead" became a runaway bestseller. Some people have the idea that Microsoft is fated to dominate technology forever, They had the same idea about IBM\ once admired and feared nearly as much as Microsoft is today. As for Gates himself he is a man who likes computers very much. Not their intellectual underpinningsnot the physics or electronics, not the art or philosophy or mathematics of software - just plain computers. He is crazy about them. It seems like an odd passion but after all some people are crazv about potato chips« VisiCalc* - one of the first programs of electronic table (spreadsheet); is out-of-date now. the Apple II* * - a microcomputer.

Шестой текст

The Elements of Computer System

Computers are electronic machines which accept data in a certain form, process the data and give the results of the processing in a specified format as information. Three basic steps are involved in the process:

1. data is fed into the computer memory;

2. when the program is run, the computer performs a set of instructions and processes the data;

3. we can see the results (the output) on the screen or in printed form. Information in the form of data and programs is known as software and the electronic and mechanical parts that make up a computer system are called hardware.

A standard computer system consists of three main parts: the CPU (Central Processing Unit), the main memory and the peripherals. The most influential component is the CPU. It executes program instructions and coordinates the activities of all the other units. In a way, it is the "brain" of the computer. The main memory holds the instructions and data which are currently being processed by the CPU The peripherals are the physical units attached to the computer. They include storage devices and input/output devices. Storage devices (floppy or hard disks) provide a permanent storage of both data and programs, Disk drives are used to handle one or more floppy disks. Input devices enable data to go into the computer's memory. The most common input devices are the mouse and the keyboard. Output devices enable us to extract the finished product from the system. The computer shows the output on the monitor or prints the results onto paper by means of a printer. On the rear panel of the computer there are several ports into which we can plug a wide range of peripherals: modems, fax machines, optical drives and scanners. These are the main physical units of a computer system, generally known as the configuration.

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Седьмой текст

Robots

Warm-up: What do you know about actual robots?

Many people may think that the contemporary industrial robot is the product of high technology but it was invented to meet a rather mundane* need. In the early 60s it became increasingly difficult to find people willing to do boring, repetitive and unpleasant jobs. What was needed was the machine which could perform sequences of the precise movements of the arm and hand. Such sequences were relatively easily programmed into a computer memory, especially after the invention of the microprocessor. This invention made robots independent from the giant mainframe computers of the 1960s, Many machines can perform repetitive manipulation but robots differ from them as they make use of a manipulator arm analogous to the human arm and because they can be reprogrammed to perform many different tasks without the need to redesign its mechanical components, Whatever its task, a robot is dependent for its effectiveness upon automated environment and it has so far restricted robot use to large scale industry. Specialist machine shops, producing small batches of many different items have little wish to set up a lot of devices which a robot requires. Automation, achieves its really spectacular success when rt abandons the attempt to do things in ways based on human skills and finds solutions that are quite new and intrinsically mechanical. Replacing wire circuits, which are impossible for machines to assemble, with printed circuits which machines can manufacture with ease is an obvious example. The robot provides an economic and relatively reliable substitute for human labor while also having a degree of flexibility that is attractive. What has yet to be established is that robots have the potential in them to advance from the status of blind preprogrammed serfs to that of a skilled and adaptive labor force, capable of learning new tricks and acting on their own initiative without the need for human interference at every stage.

The serious purpose in promoting the advance of robot technology which in recent years has not advanced as rapidly as it should have, lies behind the ingenious idea of organizing the World Robot Championships. This idea belongs to Dr Peter Mowforth from Glasgow's Turing Institute which is one of the world's leading centers of research in artificial intelligence and robotics. Besides trade exhibitions, contests seminars and workshops the robots' designers suggest even giving a celebration concert performed by a robot orchestra. mundane* — simple, plain, boring

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Восьмой текст

Multiple Meaning

Warm-up: What makes English easy to learn? What makes it difficult?

What words with multiple meaning have you come across? Are they nouns, verbs, prepositions or ... ? Name some of them.

Most of the science students think that nearly every word in English has just one meaning. This is, of course, completely contrary to the fact/A glance at any English dictionary will show this. The student will frequently find seven or eight meanings listed for quite "simple'' words. Why do they make such a mistake? One reason may be because they are science students. Scientists try to use words in their special subject which have one meaning and one meaning only. Practically all the students think that every word in English has an exact translation equivalent. Again, this is far from the truth. Sometimes one word in English can only be translated by a phrase in the student's native language. Certainly, the idea of a one word for one word translation is completely false. Translation machines which tried to work on this principle failed completely.

A great number of students believe that as soon as they know the meaning of a word, they are able to use it correctly. This is untrue for any language but is perhaps particularly false for English. Some words in English mean almost the same but they can only be used in certain situations. To make life easier you can go out right now and buy a machine translation system for anything between $100 and $100,000. But how do you know if it's going to be any good? The big problem with MT systems is that they don't actually translate: they merely help translators to translate. Yes, if you get something like Metal (very expensive) or GTS (quite cheap) to work on your latest brochure, they will chum out something in French or whatever, but it will be pretty laughable stuff. All machine-translated texts have to be extensively post-edited (and often pre-edited) by experienced translators. Analyzing the errors made by MT systems is inconclusive because it may only show that different systems produce similar numbers of different error types. For example, one of the researches conducted in Stuttgart found that one large system could cope with various complex verb-translation problems in a relative clause of a sentence, but it fell apart when trying to do exactly the same thing in a main clause of a sentence.

Good human translators produce good translations; all MT systems produce bad translations. But assessing machine translations as good or bad is very difficult because such judgments cannot -be made scientifically. Better tests are needed to monitor linguistic weaknesses in MT systems. One traditional assessment technique involves a bunch of people scoring translations on various scales for intelligibility ("Does this piece of English make sense as a piece of English?"; accuracy ("Does this piece of English give the same information as the French original?"); style, and so on. The things are different in Japan, though. The Japanese have a few independent MT training schools, which are said to be very-efficient But the European specialists share the opinion that a reliable MT system is unlikely to be available this century.

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Девятый текст

Stop the World!

The fax is spewing out a 50-page document, the mobile phone is ringing again, there are 20 e- maiis to answer to and the Internet has found 11,000 articles on the subject you are researching. A recent survey commissioned found that a lot of managers questioned were suffering from information overload and that new technology, instead of making their job easier, was causing stress, less job satisfaction and a greater degree of illness, such as headaches and stomach pains. Almost all the managers believe the Internet is making the situation worse and admitted they were unable to handle the amount of information they receive on a daily basis and said that dealing with so much information frequently meant staying late at work or having to take work home. Our ability to generate information has simply exceeded our ability to review and understand most of it, let alone to decide on priorities. More information has been produced in the past 30 years than in the past five millenniums. The fact that not all of it is of equal importance means that it needs to be sifted first. The growth of computer technology is also fuelling la worldwide 'epidemic' of shyness. We are at the beginning of a new fice age' of noncommunication. The growing use of e-mail and the disappearance of jobs such as shop assistants means that face-to-face conversations are becoming a rarity and it may well soon be possible to go through the entire day without talking to another person directly. Less and less time is spent on personal hobbies, holidays and with friends and relations. We are sending information but not conveying emotion. Computers have eroded the opportunity for small talk and this means that people now feel they need a serious reason to start an everyday conversation. From Reuters Business Information Survey

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Десятый текст

Have I Told You Lately That I Hate Windows?

Windows has again made my life hellish. A couple of weeks age I had a significant event with my computer. It left me feeling helpless and out of control For years, as I've been using personal computers and becoming a technology expert, I've been able to believe that I was in control. Now I realize it was all an illusion. When my computer crashed on Friday, May, 28, it dragged my dreams down with it. And it is Microsoft's Windows which is to blame. This operating system is so complicated that it has become unusable by mere mortals or even by geeks* like me. Windows was bearable when the thing controlled just my desktop - now that it's the chokepoint between me and the Internet, it's unmanageable. My journey into digital despair began when I bought a new computer and then tried to upgrade some software. Windows has become so complicated that it is nearly impossible to switch from one Windows computer to a newer Windows computer without losing at least some configuration information — and some key personal data. Windows does next to nothing to make it easy for you to move configuration data from one computer to another. My problems weren't limited to switching computers. I recently bought a new hand-held organizer, the Palm V. Installing its software was simple. But being a good geek, I thought I'd better upgrade to an even more current version of the software. When I did so I made one stupid mistake: ignoring the software's warning to be sure the Palm V's cradle was connected to the computer while I upgraded. Since I ignored that warning, the software reconfigured my computer in a way that neither I nor even our IT specialists at work could change. That stupid little upgrade error started the deluge. One failure cascaded upon another. I couldn't collect my e-mail or update my schedule. I couldn't update my financial accounts or pay my bills electronically. I couldn't synchronize my personal information with my Palm V, I lost faith in the fabulousness of personal computing.

*a geek— here: a stupid\ inexperienced user By Stewart Alsop, Fortune,July 1999

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Одиннадцатый текст

The World's New Millennium

A thousand years ago, when mankind approached the end of the first millennium, some pCC^l? feasted, some people prayed, some people thought the world was coming to an end — and the vast majority thought nothing of it at all because they had very little grasp of the calendar. But the 20th century, which began as the Century of Total War and grew into the Atomic Era seems to be ending as the Age of Entertainment. And the 21st century offers prospects well worth celebrating. Science and medicine, surely the two great success stories of the past 100 years, are poised for fresh advances, exploring both the unimaginable frontiers of the universe and the microscopic secrets of the human body and the potential of computers has transformed our work habits, our politics, our style of life. International affairs, though speckled with trouble spots, have settled for the moment into what might be called a PAX ECONOMICA, as rich and poor nations alike work together. The portents of the future do seem much more favorable now than at most stages of a century disfigured with blood and ruin. Predicting the future has always been a risky business. Historically, the great discoverers and inventors were often regarded by their contemporaries as quacks or even heretics. In 1930, American rocket researcher Robert H. Goddart and a group of colleagues were given a grant of $25,000 by philanthropist Daniel Guggenheim to develop rocket technology to carry scientific instruments into earthy upper atmosphere. But, fearful of losing their professional reputations and being branded cranks, the scientists emphatically denied the possibility of ever reaching the moon. In 1977 Ken Olson, founder of Digital Equipment Corp., saw "no reason why anyone would want a computer in their homeff. Now many people around the world can't live without them.

But true pioneers - people like Socrates, Voltaire, Newton-and Einstein -have consistently had the courage of their convictions; the vision to ask the right questions and the determination to keep on asking until they got satisfactory answers. Some may welcome the projected developments listed here as important advances in our knowledge of the world and our ability to improve the quality of7 our lives; others may consider them of questionable merit and regard them with some alarm. In either case, it is clear that the pace of innovation is quickening as we enter the 21st century. HERFS WHAT SCIENTIFIC PROGRESS HAS IN STORE FOR US IN THE COMING CENTURIES:

2005 - The active contact lens, linked to the Internet, allows the wearer the read E-mail and surf the World Wide Web without even opening their eyes.

2006 - Clothes made from smart fabrics automatically warm up the wearer in cold weather and cool him or her down in hot weather.

2007 * New cars are equipped with anti-collision radar, thermal imaging systems to improve visibility, on-board computers that detect and warn drivers about imminent faults, and satellite-based automatic global positioning systems.

2010 - Robotic pets, programmed to recognize their master's voice and face, operate and control all the computerized functions of the household.

2016 - The holographic telephone projects a life-size holographic image of the person being called.

2025 - Computers connected directly to the brain are able to recognize and respond to thoughts, obviating the need for the manual input of data and commands.

2030 - Human hibernation is used for the first time in long-distance space travel.

2044 - Microscopic robots capable of reproducing themselves are devised using nanotechnology.

2050 - From an average of 78 years, human life-spans are extended to 140 years. By Kate Noble, TIME, July 2000

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Двенадцатый текст

Your wish is my machine code

Writing software is a painstaking business in which you can't afford to slip up: get a single cnmaCle: wrong and the instructions either do nothing or go horribly wrong. Now a new system that takes the drudgery out vasmg is about to be launched. Its inventor hopes it will one day

turn us all into programmers. u

Bob Brennan, a software engineer at Cambridge-based start-up Synapse Soiutions, ;.Tias developed a piece of software that allows you to write a program by keying in what you want it to do in everyday language, Dubbed MI-Tech -'short for machine intelligence technology -the software translates a typed wish list into machine code, the basic mathematical language understood by the microprocessors inside computers. But this is no easy task, because everyday language is riddled with double meanings. "MI-Tech can resolve these riddles," claims Brennan, because it has been taught about the significance of context in the English language.

At the heart of MI-Tech is a store of logical rules. These allow it to extract instructions from statements in ordinary language, which it then translates into machine code. In its present form, MI- I Tech has a limited lexicon of only a few hundred words, but Brennan claims this is sufficient for

most of the tasks you might ask it to carry out. Brennan says his program can write code in a fraction of the time that it takes trained programmers. He spent months writing a program manually, producing hundreds of pages of code. But given fjust three pages of monologue", MI-Tech generated a program that performed exactly the same tasks.

Brennan is not going into any detail about how the system works until his patents are granted. But he hopes to be licensing his program to software companies within 18 months so that they can build it into their own packages. If that happens, you might well be able to add programs of your own design to your PC - without knowing how to code. By Duncan Graham-Rowe

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Тринадцатый текст

Computer Languages

Computers can deal with different kinds of problems if they are given the right instructions for what to do. Instructions are first written in one of the high-level languages, e.g. PL/I, PASCAL, • BASIC or C, depending on the type of problem to be solved. A program written in one of these languages are often called a source program and it cannot be directly processed by the computer until it has been complied, which means interpreted into machine code. Usually a single instruction written in a high-level language, when transformed into machine code, results in several instructions.

In the history of computing there have been a number of high-level languages, some of which are not being used now. The first computer language was FORTRAN, which consisted of algebraic formulae and English phrases, it was first introduced in the United States in 1954. ALGOL is acronym for ALGOrithmic Language, first introduced in Europe in 1960. PL/I, developed in 1964, is used for data processing as well as scientific applications. BASIC acronym for Beginner's All-purpose Symbolic Instruction Code was developed in 1965 at Dartmouth College in the United States for use by students who require a simple language to begin programming. The

programming language С was originally designed for Unix operating systems. It was developed basically by a man called Dennis Ritchie at Bell Laboratories in the States in 1972. Well, it was called 'C because it replaced the language used to produce the original version of Unix which was I called 'B?.

С is very popular today because itfs small, so ifs not too hard to learn, it's very efficient and it's portable so you can use it with all kinds of computers. A lot of software engineers use С to write systems software and commercial applications programs for mini, micro and personal computers. There are also new versions of С - there's С++ and Objective C. These extensions incorporate the power of object-oriented programming.

In the past, programmers had to write complex programs which covered everything you could do in text and graphics. With object-oriented programming,, however, the programmer concentrates on particular things, and gives each object specific functions which can be altered without changing the entire program.

Java itself is one of the phenomena of the 1990s computing world. It was originally the language developed to* support a larger project "Smart computer electronia devices".

The members of this project did not wish to use С or С++ due to technical difficulties with those languages: the problems associated with the construction of high-integrity software. It is interesting to note that specialists working on this project had experience not only with С and С++ but also with languages such as LISP, the P-System, PASCAL and SMALTALK. August 1991 can be treated as the birth of this new language, as it was at this time that a basic set of classes and a compiler were made available. This new language was known as OAK. There was a rumor that this name was given to the newly-created language after the tree outside the team leader's office. By the end of 1993 having discovered that there was no demand for the intended product SUN decided to drop the project and disband the team. However, in mid-1993, the interest in the Internet and in particular the World-Wide Web, was growing and it became clear that the software language the team had developed might well be perfect for the Web. They managed to convince Sun that it would be worth funding the software part of the project and Sun invested $5 million into the software development during 1994.

In mid-1994, OAK was used to build a new Web browser, which went on to be called HotJava. This illustrated the potential of the language by allowing animated (rather than static) Web pages. As the language was designed to be portable, secure and small, and to operate in real time, it was ideally suited to the sort of environment that the Web imposed. During this period OAK was renamed Java. In early 1995 Java was launched on an unsuspected public at the first Java Day. Although there is little new in Java, the resulting language is more than the sum of its parts. It supports concurrency, dynamic linking of new code, automatic memory management, compilation to byte codes, platform independence and strong typing. It is also worth noting that it is an excellent object-oriented programming language in its own right.

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Четырнадцатый текст

Programming

Programmers use a logical series of procedures to write a program. The main steps involved in programming are:

First, the programmer has to analyze the problem and define the purpose of the program. The task must be restated as a precise list of events leading to a solution.

Secondly, he has to design an algorithm, which is a step-by-step plan that describes these events in a simple logical sequence. This plan usually takes the form of a flowchart which is a diagram that uses standardized symbols showing the logical relationship between the various parts of the program. These special symbols show how the computer works through the program - where it makes decisions^ where it starts and ends, and things like that.

Later these logical steps are translated into instructions written in the computer language used for that program. This is called "coding". The program is then "complied", which means that the high- level code is translated into binary code, the only language that computers understand. The function of compilers is to convert a source program into an object program. Compilers convert a program written in a high-level language into a program written in a lower level language. Special test programs can be run to detect errors or 'bugs' in the program. This process is called "debugging". The programmer must trace each error back to its origin, then write the correct instruction, re¬compile the program and conduct another series of test runs. Debugging continues until the program runs smoothly. Finally, the programmer writes documentation for the user. Manuals provide instructions on how to use the program.

With a database you can store, organize and retrieve a large collection of related information on computer. Information is entered on a database via fields. Each field holds a separate piece of

information and the fields are collected together into records. Records are grouped together into files which hold large amounts of information. Files can easily be updated: you can always change fields, add new records or delete old ones. With the right database software, you're able to keep track of all the details that can make you successful Another feature of database programs is that you can automatically look up and find records containing particular information. If we had to summarize the most relevant advantages of a database program over a card index system (a catalogue), we would say that the former is much faster to consult and update, occupies a lot less space and records can be automatically stored into numerical or alphabetical order using any field. The best packages also include networking facilities, which add a new dimension of productivity to business. Thanks to security devices, you can share part of your files on a network and control who sees the information. Most aspects of the program can be protected by user-defined passwords. Such features like mail merging, layout design and the ability to import and export data are also very useful.

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Пятнадцатый текст

Basic Uses of the Internet

I. The information superhighway, or the Internet, is the world's largest computer network. It is a network made up of thousands of smaller networks. The purpose of the Internet is to exchange information and improve communication.

The concept of the superhighway communication system started back in the 1960s when the threat of cold war was looming and the United States government worried about how people would communicate in the event of war.

In 1969 The United States formed ARPANET to link defense contractors and universities doing defense research together using computers. This permitted instant communication, but the system soon grew too big for the military to handle on their own. More academic institutions became involved, and the network expanded to include academic and research facilities around the world. There are now millions of users and hundreds of thousands of host computer networks in over 135 countries around the world.

The Internet can be used in many ways, but the three most common functions are electronic mail or e-mail, gopher and File Transfer Protocol or FTP.

To join the Internet you need some kind of computer, but which is more or less irrelevant. So, you might be using a powerful Unix-based workstation, a PC running Microsoft Windows, an Apple Macintosh, or an Atari: all of these can be used without problem since the Internet was built specifically to interconnect the most disparate kinds of computers. Nor does the speed of the computer matter that much: the Internet is about communications, and involves using the power of other computers located elsewhere. Your own will be largely engaged in sending instructions to other, probably more powerful, machines (this is usually known as the client-server model, where the computer you use is the client which sends requests to a server, in this case generally located elsewhere on the Internet).

There are good reasons for choosing a reasonably powerful machine. First, it will let you run all the most up-to-date software: it is largely through a new generation of easy-to - use Windows software that the Internet has suddenly become accessible to everyone. Some of these new programs are quite large and make greater demands on the PC than older software. For example, the Windows 95 operating system comes with many Internet elements already built-in, but requires more hardware power than earlier versions of Windows. Similarly, the bigger your hard disk is, the more you will be able to explore the Internet. The reason for this is simply that you will find so much to download that disk space may prove to be a constraining factor on your explorations. In any case, hard disk costs have fallen so dramatically in recent years that even a disk with a capacity of many hundreds of Mbytes is now reasonably priced. To use your personal computer on the Internet, you need some way of connecting it. By far the commonest method of effecting a link between you and the global online community is to use the telephone.

Typically you will use a modem to connect your computer to the dial-up line (there are other options like ISDN - Integrated Services Digital Network - but the principles remain the same.) Whereas the power of your personal computer does not affect too much the speed at which you can access the Internet, your choice of modem does, critically. For this reason, if you intend using the Internet for anything more than the simplest e-mail you are strongly advised to buy a fast modem. Fast in this context means one that has a basic throughput of 14400 bits per second. In fact, with аду kind of normal use a faster modem will pay for itself in a few months: the greater throughput means that you will spend much less time on the phone downloading files, and the resulting savings on the phone bill will quickly cover any extra cost for the modem. From The Internet with Windows1, 1996

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Шестнадцатый текст

The Internet via Cable

Warm-up: What means of transmitting information do you know? Put them in chronological order: oral messages, letters... What are the latest achievements?

Using cable Internet services for the first time can be a breathtaking experience. Images and text flash before your eyes instantly. Full-motion video and audio play without jitter. Whoa you see this, you realize that this was how the Internet was meant to be. Even for Internet old-timers, it's like a whole new world.

The cable television network has emerged as the early leader in providing such high-speed data access in the home. With more than a million cable modem subscribers now in North America, the system has matured from a string of experimental deployments in 1995 to a main-stream service available in most major cities.

Internet access over cable runs at speeds up to 100 times those of the traditional dial-up world. And the connection is "always on", enabling users to call up a site immediately as the spirit moves them. Gone are the days of having to log in to the network. How does cable achieve these data rates? In the late 1980s and early 1990s cable operators started deploying fiber optics in their networks. Cable companies ran fiber out to individual neighborhoods and made use of the existing network of coaxial cable - the familiar line that screws into your TV - to reach the "last mile" to each home. The optical fibers connect the cable operator's central facility (the "head end") to each neighborhood area (the "node"), which typically encompasses about 1,000 homes, each a potential customer. Fiber has greatly increased the capacity and cable TV networks. With a cable Internet connection, data occupy the space of one TV channel. Tune to this channel with your TV, and you'll see only static, but connected to your cable modem it becomes a data stream flowing at about 40 mega-bits per second, which can then be relayed to your personal computer at rates up to 10 megabits per second. The fiber network also allows signals to be sent back from the home to the head end, making telephone and interactive video services possible. About half of all North American cable homes already have this two-way capability, fewer in Europe and Asia.

A cable modem can connect to more than one PC in the home, with excellent support for in- home networks. Cable modems use a number of advanced techniques to perform their duties. In fact, "cable modem" is a bit of a misnomer, because it has several additional roles: directing traffic, encrypting for security, validating signals and tuning the proper channel. Automated software updates for the modems can be centrally coordinated, and service anomalies can be flagged without human intervention. Early-warning signals from the modems let the provider respond to problems before they affect service.

Cable modems will enable a wide variety of services. But what really thrills television executives is the integration of TV with the Internet allowing subscribers to move back and forth seamlessly, from one medium to the other. For instance, while you're watching a film you could have a window open on your TV for chatting with other viewers about what's happening on the screen. And someday soon images, sounds and data from all over the globe may come at you at remarkable rates, and you will realize that what you're experiencing is not your fathers cableTF network. By MiloMedin and Jay Rolls from 'Scientific American1, October 1999

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Семнадцатый текст

What is an E-Mail?

The most frequently used function of the Internet is e-mail. It is probably the easiest of the functions to learn to use effectively. E-mail provides almost instant communication with others on the system worldwide. With e-mail you never get a busy signal. The message arrives at a computer and waits for the receiver to respond.

In order to use e-mail each user must have their own unique user name. The way user names are formed is decided by each institution. For example at Concordia all user names begin with the prefix CRF, then we use the first six letters of our last name and our first and middle initials. The user name is followed by an @ sign. Following the @ will be the node, domain and type names. Each node will also have an unique name. Each organization decides its own node and domain names. There are several different type names, which are standard: Commercial = com; Educational ~ edu; Government - gov; Military = mil; Organization = org.

Many people now include their e-mail address when sending standard communications,, What is very nice about the Internet is that as soon as you send a message your address is automatically placed at the top of the message so the receiver knows who sent it. Ifs an automatic return address. You can usually figure out where someone's message is coming from by looking at the node and domain names. For very good reasons some organizations have unusual domain names and determining the origin of the message is more difficult. Northwestern University, for example, uses CASBAH as its domain name and the University of Virginia uses DAYHOFF. Making the connection: The first thing you do is to log into уодг system. Once you have logged in you may enter the mail system. There are many different mail software packages available. Current e-mail software is getting easier to use with each new version. Some are menu driven and others require you to know and type the command. There are other things you can do with e-mail List serves provide a discussion forum for people with similar interests. You can gain access to these forums by subscribing. Simply send an e-тщ! message to tb address given for the listserv and ask to be added to the subscription list. Sometimes a given e-mail address doesn't work. When that occurs, there are two possibilities. One is that the address has changed. Remember, thai the Internet changes from day to day, and so do its addresses. You need t remain very flexible when you work with list serves. The second possibility is that it may be necessary to use a gateway to get into listserv. A gateway is a computer that connects two types of networks an automatically converts the protocol used in those networks. Newsgroup are also available on some systems. They are like reading a newspaper every day. Newsgroups require special software to read the messages.