Is Today the Internet's 40th Birthday?

On this day 40 years ago, first message sent between two campuses.

October 29, 2009, 9:48 AM

Oct. 29, 2009— -- Happy Birthday, Internet?

While the actual date of the Internet's birthday is somewhat debated, many say that the Internet was born 40 years ago today at the University of California, Los Angeles, when a computer to computer message was sent for the first time from the UCLA campus to Stanford.

At the time, Leonard Kleinrock and his colleagues were charged with developing the Advanced Research Projects Agency Network (or ARPANET), a government-funded research project in global computer communications that eventually grew into the Internet.

On Sept. 2, 1969, Kleinrock and his team succeeded in getting two computers to exchange data over a network for the first time, creating the first node of what we now know as the Internet. Some consider that to be the Internet's first moment of life.

But Kleinrock considers his team's feat 40 years ago today to be "the first breath of life the Internet ever took." The message he intended to send to Stanford was "login" but Kleinrock was only able to type "lo" before the system crashed. On his second attempt, the message went through successfully.

In honor of the occasion, Kleinrock and his colleagues are celebrating today with a day-long event featuring speakers and panels on UCLA's campus.

It's hardly surprising that a system so complex has a hard-to-pin-down date of birth and many say either date suffices.

"It's valid to consider either one because each involved transmission between computers," said Michael A. Banks, a technology writer and author of "On the Way to the Web: The Secret History of the Internet and Its Founders."

Since its academic beginnings, the Internet has come a long way, revolutionizing nearly every aspect of human interaction.

In honor of the occasion, here's a walk down memory lane and a look at some the Internet's most significant milestones.

Why? "Mostly because it seemed like a neat idea," he has said.

ARPANET Goes Global, Grows Into the Internet

These services marked a "really big step" in bringing consumers ? not just academics and government officials ? online, Banks said. Although the users couldn't communicate with users of other networks or access information hosted on other networks, they still formed some of the first vibrant emerging online communities.

"Lives were changed immediately. People stayed online longer and later, fascinated with the ability to interact with several people at once," Banks writes in his book, "On the Way to the Web." "The online world and its denizens took on a new aura of reality, and the online experience grew far more entertaining and unpredictable."

He was sentenced to three years' probation, community service, and a fine of $10,000 plus legal costs. Despite his run-in with the law, he went on to great success, eventually joining a startup that was bought out by Yahoo.

Now, he's a professor in the Computer Science and Artificial Intelligence Laboratory at M.I.T.

Tim Berners-Lee Introduces the 'World Wide Web'

While working at CERN, the European Organization for Nuclear Research, he devised the Web as a way to organize, address and link information on the Internet.

Smart Phones Bring Mobile Internet to Millions

"When it launched it was a Facebook replacement for college. The day it became a genuine platform was when they opened it up," said Harvard's Weinberger.

The Associated Press contributed to this report.

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