Computers
Unlike technologies such as the
light bulb or the telephone, the Internet has no single “inventor.” Instead, it
has evolved over time. The Internet got its start in the United States more
than 50 years ago as a government weapon in the Cold War. For years, scientists
and researchers used it to communicate and share data with one another. Today,
we use the Internet for almost everything, and for many people it would be
impossible to imagine life without it.
The Sputnik Scare
On October 4, 1957, the Soviet
Union launched the world’s first manmade satellite into orbit. The satellite was
known as Sputnik. 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.
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
the1970s. 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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