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(单词翻译:双击或拖选)
EXPLORATIONS - October 23, 2002: Information Age, Part 2
By Paul Thompson
VOICE ONE:
This is Mary Tillotson.
VOICE TWO:
And this is Steve Ember with the VOA Special English program, EXPLORATIONS. Today we present the
second part of our series about communications. We tell how computers are linking many millions of people
around the world.
(THEME)
VOICE ONE:
Last week we told about the history of the communication of information. We
described how the telegraph1 was the first important device2 that could move
information quickly from one place to another. And we discussed the beginning of
satellite communications.
About six years after the first communications satellite was placed in orbit3, the
American Department of Defense4 began developing a new project. It began linking
major research universities across the United States. The project began in the early nineteen-seventies.
VOICE TWO:
Professors at many American universities do research work for the United States Government. The Department
of Defense wanted to link the universities together to help the professors cooperate5 in their work. Department of
Defense officials decided6 to try to link these universities by computer. The officials believed the computer would
make it easier for researchers to send large amounts of information from research center to research center. They
believed they could link computers at these universities by telephone.
VOICE ONE:
They were right. It became very easy to pass information from one university to another. University researchers
working on the same project could share large amounts of information very quickly. They no longer had to wait
several days for the mail to bring a copy of the research reports.
VOICE TWO:
This is how the system works7. The computer is linked to a telephone by a device called a modem8. The modem
changes computer information into electronic messages that are sounds. These messages pass through the
telephone equipment to the modem at the other end of the telephone line. This receiving modem changes the
sound messages back into information the computer can use. The first modern electronic communication device,
the telegraph, sent only one letter of the alphabet at a time. A computer can send thousands of words in a very
few seconds.
VOICE ONE:
The link between universities quickly grew to include most research centers and colleges in the United States.
These links became a major network. Two or more computers that are linked together form a small network.
They may be linked by a wire from one computer to another, or by telephone. A network can grow to almost any
size.
(Photo -NASA)
For example, let us start with two computers in the same room at a university. They are linked to each other by a
wire. In another part of the university, two other computers also are linked using the same method. Then the four
are connected with modems9 and a telephone line used only by the computers. This represents a small local
network of four computers.
Now, suppose this local network is linked by its modem through telephone lines to another university that has
four computers. Then you have a network of eight computers. The other university can be anywhere, even
thousands of kilometers away. These computers now can send any kind of information that can be received by a
computer - messages, reports, drawings, pictures, sound recordings10. And, the information is exchanged
immediately.
VOICE TWO:
Some experts have said it is easier to understand this network of computers if you think of streets in a city. The
streets make it possible to travel from one place in the city to another. Major streets called highways connect
cities. They make it possible to travel from one city to another.
Computers communicate information in much the same way. Local networks are like the city streets. And
communication links between distant local networks are like the major highways. These highways make
communication possible between networks in different areas of the world.
VOICE ONE:
In nineteen-eighty-one this communication system linked only two-hundred-thirteen computers. Only nine years
later, it linked more than three-hundred-fifty-thousand computers. Today experts say there are hundreds of
millions of computers connected to networks that provide links with computers around the world.
The experts say it is no longer possible to tell how many computers are linked to the information highway. The
experts also say the system of computer networks is continuing to grow.
VOICE TWO:
This system of computer networks has had several different names since it began. It is now called the Internet.
Almost every major university in the world is part of the Internet. So are smaller colleges and many public and
private schools. Magazines, newspapers, libraries, businesses, government agencies11, and people in their homes
also are part of the Internet.
VOICE ONE:
Computer experts began to greatly expand the Internet system in the last years of the nineteen-eighties. This
expansion12 was called the World Wide Web. It permits computer users14 to find and exchange written material and
pictures much quicker than the older Internet system. How fast is the World Wide Web part of the Internet
system? Here is an example. A computer user13 in London, England is seeking information about the volcanoes16 in
the American state of Hawaii.
She types in the words “Hawaii” and “volcano15” in a World Wide Web search program. Within seconds the
computer produces a list. She chooses to examine information from the National Park Service’s headquarters17 at
the Hawaii Volcanoes National Park. The Park Service computer in Hawaii provides information about the huge
volcanoes there, and how they were formed. It also has other useful information.
The researcher in London looks at the information. Then she has her computer print a copy of it. Within seconds
she has a paper copy of the National Park information including pictures. It has taken her less than five minutes
to complete this research.
(MUSIC BRIDGE)
VOICE TWO:
The Internet and the World Wide Web have become vehicles for speedy information exchange for most people
who can use a computer. Much of the information on the Internet is very valuable. As a research tool, the Internet
has no equal.
Suppose you want a copy of this Special English program, EXPLORATIONS. You can find the information by
looking for the Voice of America and Special English on the World Wide Web. The electronic address is www
dot voa special english dot com. (www.voaspecialenglish.com) You can find written copies of most of our
programs and print them for your own use.
Almost any kind of information can be found through the Internet. There are electronic magazines for poetry or
children’s stories.
There are areas within this electronic world where you can play games or discuss politics or science. You can
find valuable medical information, read history, learn about new farming methods or just about anything that
interests you. You can look at and collect the beautiful color pictures taken by the Hubble Space Telescope.
You can watch musicians perform their latest songs. You can even join a group that meets electronically to
discuss the music of their favorite rock and roll music group.
VOICE ONE:
Who pays for the Internet? That is not easy to explain. Each network, small or large, pays for itself. Networks
decide how much their members will pay for their part of the cost of the local service connecting time.
Then all of the large networks decide how much each will pay to be part of the larger network that covers a major
area of the country. The area network in turn pays the national network for the service it needs.
Each person who has a computer at home pays a company that lets the computer connect to the Internet. These
companies are called Internet service providers. Most charge less than twenty dollars a month for this service.
VOICE TWO:
Next week the EXPLORATIONS program will examine the future of the Internet and the World Wide Web. We
will tell about modern technology that lets networks link with telephones that do not need wires.
(THEME)
VOICE ONE:
This Special English program, EXPLORATIONS, was written by Paul Thompson. It was produced by Caty
Weaver18. This is Mary Tillotson.
VOICE TWO:
And this is Steve Ember. Listen again next week to the Voice of America for the last part of this series about the
Information Age.
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1 telegraph | |
n.电报,电报机;v.打电报,显示 | |
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2 device | |
n.器械,装置;计划,策略,诡计 | |
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3 orbit | |
n.轨道;vt.使沿轨道运行;使进入轨道运行;vi.沿轨道运行,环行 | |
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4 defense | |
n.防御,保卫;[pl.]防务工事;辩护,答辩 | |
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5 cooperate | |
vi.合作,协作,相配合 | |
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6 decided | |
adj.决定了的,坚决的;明显的,明确的 | |
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7 works | |
n.作品,著作;工厂,活动部件,机件 | |
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8 modem | |
n.调制解调器 | |
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9 modems | |
n.调制解调器( modem的名词复数 ) | |
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10 recordings | |
n.记录( recording的名词复数 );录音;录像;唱片 | |
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11 agencies | |
n.代理( agency的名词复数 );服务机构;(政府的)专门机构;代理(或经销)业务(或关系) | |
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12 expansion | |
n.扩张,扩充;扩大;扩充物;扩展部 | |
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13 user | |
n.用户,使用者 | |
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14 users | |
用户,使用者( user的名词复数 ) | |
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15 volcano | |
n.火山 | |
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16 volcanoes | |
n.火山( volcano的名词复数 ) | |
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17 headquarters | |
n.司令部,指挥部;总部,总店 | |
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18 weaver | |
n.织布工;编织者 | |
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