The Internet─one single word names a revolution in communications and computer technology.
Emails arrive almost instantly. Online shoppers order everything from books to cars without leaving their homes.
Families share photos from across the world.
Massive amounts of information flow from one part of the world to another, as easily as water flows downhill.
The Internet has changed our lives. But how did this complex system of billions of webpages,
which are viewed by millions of people every hour of every day, begin?
The Internet is made up of many computer networks, and it began in 1969 with the network called ARPANET.
ARPA stands for the Advanced Research Projects Agency, which is part of the United States Department of Defense.
ARPA was responsible for organizing the defense department's research.
ARPA needed a way to send and receive vast amounts of information all over the United States.
Unfortunately each of the universities and businesses doing research for ARPA had its own computer system;
these systems could not communicate with each other.
ARPA decided to solve this problem by creating standard rules for these computers to communicate.
The result was ARPANET, which was the first computer network to link computers over long distances.
Eventually universities started to use this network for their own purposes,
and it was not long before university students as well as professors had their own email addresses.
As the network grew and more and more computers were connected, it became the Internet.
The communication standards developed by ARPA are called protocols.
The word "protocol" comes from the world of diplomacy.
In diplomacy, following protocol means following the precise rules for meeting or communicating with governments, their ambassadors, and their rulers.
ARPA invented the protocols that allow computers to exchange information over the Internet.
Transmission Control Protocol (TCP) checks that every piece of information a computer sends is complete.
It is TCP that stops a computer from getting confused about what information is an email and what is a webpage.
Internet Protocol (IP) ensures that every transmission is sent via the correct route and that the right data arrives at the right computer.
Not all computers are connected all the time, and often they receive more data than they can handle.
For data traveling on the Internet, this can be like finding a road blocked or getting stuck in a traffic jam.
But Internet Protocol makes sure that every piece of data takes the fastest route to its destination.
In its early years, the Internet was used only by scientists and other academics and was limited to a few simple functions,
such as email and file transfers.
As more universities linked their computers together, researchers wanted a way to access one online document directly from another.
It was a difficult task; a system was needed to send any file to any computer in the world, and then automatically display the needed information.
Tim Berners-Lee was a computer programmer at the European Organization for Nuclear Research (CERN) in Switzerland.
He wanted to make the Internet easier to use and help researchers share information.
In 1989 he invented the Uniform Resource Locator (URL) and HyperText Markup Language (HTML).
HTML is the language used to write webpages, and URLs indicate the location of files on the Internet.
By creating these two tools, Tim Berners-Lee invented the World Wide Web.
He created the first website, and it is still online.
You can see it for yourself by clicking on its URL, which is http://www.w3.org/History/19921103-hypertext/hypertext/WWW/News/9201.html
The first webpages contained only text.
While a text link on a page could let you download an image to your computer, there was no easy way to display an image on a webpage.
This changed in 1991, when Marc Andreessen created Mosaic, the first user-friendly Web browser.
He went on to found the company Netscape in 1993.
Netscape sold a Web browser called Navigator, and it was a great success.
It was so successful that Microsoft built its own browser called Internet Explorer.
Microsoft included its browser for free with every copy of the Windows operating system.
Netscape complained that this giveaway was unfair competition, but the free copies of Internet Explorer gave almost everyone an easy way to go online.
With both Andreessen's browser and Berners-Lee's Web protocols, anyone could visit a webpage and, more importantly, create one.
By 1993 more than 800,000 webpages had been created.
In August 2005 over twenty billion webpages were available online.
Use of the Internet and the World Wide Web keeps increasing every year.
In 2005 almost 730 million people had access to the Internet according to one estimate.
Faster Internet speeds have also increased public and commercial interest.
So many people are online that companies are spending billions of dollars advertising on webpages.
There is so much information on the Internet that helping people search the Internet created its two biggest companies, Google and Yahoo!
The Internet is also replacing long-established technologies.
To a great extent, email has replaced letter writing.
By connecting a headphone and microphone to their computers, people can speak with each other over the Internet, replacing the need for a telephone.
Video chatting is allowing people to meet online, instead of having to fly long distances.
The Internet has changed our lives. We count on it for business and personal communication.
We turn to it for news and entertainment.
In the few short years since its invention, it has reshaped modern life.
With faster and faster speeds and new wireless technologies, who knows where it will take us tomorrow?