THE SPUTNIK
SCARE
On October 4, 1957, the Soviet Union
launched the world’s first manmade satellite into orbit. The satellite, known
as Sputnik, did not do much: It tumbled aimlessly around in outer space,
sending blips and bleeps from its radio transmitters as it circled the Earth.
Still, to many Americans, the beach-ball-sized Sputnik was proof of something
alarming: While the brightest scientists and engineers in the United States had
been designing bigger cars and better television sets, it seemed, the Soviets
had been focusing on less frivolous things—and they were going to win the Cold War because of it.
Today, almost one-third of the world’s 6.8 billion people
use the Internet regularly.
After Sputnik’s launch, many
Americans began to think more seriously about science and technology. Schools
added courses on subjects like chemistry, physics and calculus. Corporations
took government grants and invested them in scientific research and development.
And the federal government itself formed new agencies, such as the National
Aeronautics and Space Administration (NASA) and the Department of Defense’s
Advanced Research Projects Agency (ARPA), to develop space-age technologies
such as rockets, weapons and computers.
THE BIRTH
OF THE ARPANET
Scientists and military experts were
especially concerned about what might happen in the event of a Soviet attack on
the nation’s telephone system. Just one missile, they feared, could destroy the
whole network of lines and wires that made efficient long-distance
communication possible. In 1962, a scientist from M.I.T. and ARPA named J.C.R.
Licklider proposed a solution to this problem: a “galactic network” of
computers that could talk to one another. Such a network would enable
government leaders to communicate even if the Soviets destroyed the telephone
system.
In 1965, another M.I.T. scientist
developed a way of sending information from one computer to another that he
called “packet switching.” Packet switching breaks data down into blocks, or
packets, before sending it to its destination. That way, each packet can take
its own route from place to place. Without packet switching, the government’s
computer network—now known as the ARPAnet—would have been just as vulnerable to
enemy attacks as the phone system.
“LOGIN”
In 1969, ARPAnet delivered its first
message: a “node-to-node” communication from one computer to another. (The
first computer was located in a research lab at UCLA and the second was at
Stanford; each one was the size of a small house.) The message—“LOGIN”—was
short and simple, but it crashed the fledgling ARPA network anyway: The
Stanford computer only received the note’s first two letters.
THE NETWORK
GROWS
By the end of 1969, just four
computers were connected to the ARPAnet, but the network grew steadily during
the 1970s. In 1971, it added the University of Hawaii’s ALOHAnet, and two years
later it added networks at London’s University College and the Royal Radar
Establishment in Norway. As packet-switched computer networks multiplied,
however, it became more difficult for them to integrate into a single worldwide
“Internet.”
By the end of the 1970s, a computer
scientist named Vinton Cerf had begun to solve this problem by developing a way
for all of the computers on all of the world’s mini-networks to communicate
with one another. He called his invention “Transmission Control Protocol,” or
TCP. (Later, he added an additional protocol, known as “Internet Protocol.” The
acronym we use to refer to these today is TCP/IP.) One writer describes Cerf’s
protocol as “the ‘handshake’ that introduces distant and different computers to
each other in a virtual space.”
THE WORLD
WIDE WEB
Cerf’s protocol transformed the
Internet into a worldwide network. Throughout the 1980s, researchers and
scientists used it to send files and data from one computer to another.
However, in 1991 the Internet changed again. That year, a computer programmer
in Switzerland named Tim Berners-Lee introduced the World Wide Web: an Internet
that was not simply a way to send files from one place to another but was
itself a “web” of information that anyone on the Internet could retrieve.
Berners-Lee created the Internet that we know today.
Since then, the Internet has changed
in many ways. In 1992, a group of students and researchers at the University
of Illinois developed a sophisticated browser that they called
Mosaic. (It later became Netscape.) Mosaic offered a user-friendly way to
search the Web: It allowed users to see words and pictures on the same page for
the first time and to navigate using scrollbars and clickable links. That same
year, Congress decided that the Web could be used for commercial purposes. As a
result, companies of all kinds hurried to set up websites of their own, and
e-commerce entrepreneurs began to use the Internet to sell goods directly to
customers. More recently, social networking sites like Facebook have become a
popular way for people of all ages to stay connected.
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