In the early nineteen seventies, the American Department of Defense began developing a
new project. It began linking major research universities across the United States

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 cooperate in their work. Department of Defense officials decided 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.They were right. It became very easy to
send 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

This is how the system works. The computer is linked to a telephone by a device called a
modem. 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 within seconds

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.
For example, let us start with two computers in the same room at a university. A wire
links them to each other. In another part of the university, two other computers also are
linked using the same method. Then the four are connected with modems and a telephone
line used only by 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 can now send any kind of information that can be received by a computer -
messages, reports, drawings, pictures, sound recordings. And, the information is
exchanged immediately

Since it began, this system of computer networks has had several different names. It is
now called the Internet. In nineteen eighty-one, this communication system linked two
hundred thirteen computers. Only nine years later, it linked more than three hundred fifty
thousand computers. Today, experts say more than one billion people around the world
are linked by computers to the Internet. And, they say, this number will continue to grow.
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 agencies, and people in their homes also are part of the Internet


Computer experts began to greatly expand the Internet system in the last years of the
nineteen eighties. This expansion was called the World Wide Web. It permits computer
users to easily search for information using software called a browser.
How fast is the World Wide Web part of the Internet system? Here is an example. A
computer user in London, England is seeking information about volcanoes in the
American state of Hawaii. She types in the words "Hawaii" and "volcano" in a search
engine, such as Google

The computer produces a list within seconds. She chooses to examine information from
the National Park Service's headquarters 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 on her computer. Then she prints a
copy of it. Within seconds she has a copy of the National Park information including
pictures. It has taken her less than five minutes to complete this research

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.
ISP's charge about twenty dollars a month for a slow dial-up connection to the Internet. A
computer user with a high-speed wireless connection pays at least forty dollars a month.
Wireless connections generally link computers to the Internet with a special technological
device called a router

The United States used to have the largest number of Internet users in the world.
However, in April, the USA Today newspaper reported that China now has the largest
number of people using the Internet. Estimates from a Chinese research group said more
than two hundred twenty million people in China were using the Internet as of February.
That is about seventeen percent of the Chinese population.
The newspaper said the United States had two hundred sixteen million Internet users at
the end of last year. That is seventy-one percent of the population. The Internet World
Statistics Web site notes several other countries where more than sixty percent of the
people use the Internet. They include Japan, Germany, the United Kingdom, Australia
and South Korea.
Studies have shown that people use the Internet for communication and for research.
Much of that research leads to buying products on the Internet. More people than ever are
now using the computer for e-commerce – to buy and sell products electronically


Some governments, private groups and individuals have criticized the Internet. Some
governments do not trust the Internet because they say it is difficult to control the
information that is placed there. Some government officials say extremist groups place
harmful information on the Internet. They say dangerous political information should be
banned. Other groups say it is difficult to protect children from sexual information and
pictures placed on the Internet. They say this kind of information should be banned.
Other critics say that it is becoming extremely difficult to know if you can trust the
information that is found on the Internet. They wonder if the information is correct. Still
other critics say the Internet is no longer a free exchange of information and ideas. They
say it has become a big business that sells products, services and information. They want
the Internet to be used only for research and education.
Next week we will examine some new technologies that have developed with the help of
the Internet. Many of these technologies are being used in education