"We lived in farms, then we lived in cities, and now we're gonna live on the Internet!"

That line, from the acclaimed movie The Social Network, is spoken by Sean Parker (played by Justin Timberlake), first president of Facebook, around 2004.

As of 2010, his "prophecy" has come true. This month, a crucial decade in the history of communications comes to an end. In just 10 years:

Internet use worldwide has exploded. In 2001, about 655 million people used it; as of this month, about 1.967 billion do, or about 28.7 percent of everyone on Earth.

Old media - newspapers, magazines, radio, CDs, movies and DVDs - have declined in favor of Web-based content, whether page-viewed, streaming, downloaded, or mobile-app.

User-generated content, a term that went mainstream in 2005 with the birth of YouTube, has increasingly come to dominate the media world. As users create more and more content, old distinctions are eroding between those who supply and those who consume. Remember: Time's Person of the Year in 2006 was "You." And you are either more powerful than ever - or helpless before forces no one can ever stop, trace, or counter.

"Every day I think about it," says Sree Sreenivasan, professor of digital media at Columbia Journalism School. "The world has changed in ways nobody could have imagined."

How it looked in 2001

Ten years ago, the Web was, well, texty. E-mail was cool. The big Internet force was America Online, mailing everyone pesky free-trial CDs. Less than 3 percent of all retail sales took place online.

But change was afoot. Home access to fast, broadband Internet service was new - but as it became cheaper and easier to get, so did the reaches of the Web.

In March 2000, less than 5 percent of those surveyed had broadband service at home, says Lee Rainie, director of the Pew Research Center's Internet and American Life Project. As of May 2010, 66 percent had it. "With easier, faster access," Rainie says, "the Internet became more and more deeply woven into people's lives."

On Jan. 15, 2001, Wikipedia was born. The online community-edited encylopedia, one of the biggest, most active, best-linked sites on the Web, now has more than 35 million articles in 200 languages (3.5 million in English alone), and 80 million-plus visitors a day. Warts and all, Wikipedia symbolizes the faith many folks place in the originality and open access of the Web.

On Sept. 11, 2001, the world was made a village by the World Trade Center attacks. Sreenivasan stresses "the way it focused the entire world on one event. People felt the need to connect, to share information, to learn instantly. That was the start of the world suddenly collapsing into a single world."

The rise of social

The Web connects us with information, goods, and services; social media connect us with one another. As Sreenivasan puts it, "One of the decade's biggest stories is the rise of social media." In 2001, there were no MySpace (born 2003), no Facebook (2004), no Twitter (2006). Today, MySpace enjoys 57 million users, Twitter more than 190 million (increasingly via mobile devices), and Facebook more than 500 million (and more than half of all U.S. traffic). Mark Zuckerberg, cocreator of Facebook, was named Time's Person of the Year for 2010.

Blogs, texts, Twitter, YouTube, Flickr, Facebook - there's a library of ways to tell the world what you're doing and thinking in words, pictures, audio, and video. These have helped birth - or, some say, destroy - notions of privacy. Zuckerberg said in a Jan. 8 speech that "people have really gotten comfortable not only sharing more information and different kinds, but more openly and with more people."

Social etiquette is changing. The first thing many people say when fielding a call is less often "Hello" than "Where are you?" As Rainie says: "You can be talking to someone, suddenly their cell phone rings, and instantly, they're with someone else! And for many of us - not all - this is now permissible and to be expected in our social worlds. We're still working out the rules as we go."

The rise of mobile

Starting from zero in 2000, today about 57 percent of adults are mobilely connected with smart phones and other devices to the Internet, says Rainie. Increasingly, social media such as Facebook and Twitter are mobile, not deskbound.

Mobile phoners do almost anything you can do on a desktop: e-mail, Web surf, upload content, download podcasts. (The word podcast is of 2004; as of 2010, there are about 58 million podcast listeners worldwide.) Ours is the era of the text message. A Nielsen study in October said the typical teen sends a text every 10 minutes, or 3,339 texts per month.

In 2001, there was no iPhone (born 2007) and no iPhone apps. But downloadable application software for mobile phones (born 1998) is banging big. In 2009, 300 million apps were downloaded worldwide - exploding to five billion this year. "App culture," says Rainie, "is becoming a sphere in itself, almost apart from the Web, where people download and customize their own particular media worlds."

A DIY world

In the emerging do-it-yourself media world, the user is star, producer, and publisher. Rainie says two-thirds of adults and three-quarters of teens create content - from commenting on websites to posting videos: "Any time you forward something to someone else, really, you've published something new."

This DIY world began with blogs. The word blog, shortened from web log, is of 1999. Sites like Blogger.com (born 2001) made it easy for anyone to create a blog. By 2002, more than 700,000 users were on Blogger.com alone. As of 2010, some estimate there are more than 400 million blogs just in English.

Videos next. Sreenivasan says, "People forget just how difficult it was to upload a simple video onto the Internet in 2000 - and how astoundingly easy it is today." The real fire-starter was YouTube (2005), which now has more than 120 million users and 245 million hits a day.

The growth of video, once the province of professionals, has changed the media landscape. "Video has joined the textual message as a major ingredient of the online community," says Matthew R. Kerbel, professor of political science at Villanova University. "The cheap video can compete with the much more complex TV message. It has a lot of small-d democratic energy in it: It's an entry point for a greater number of people, amateurs, citizens."

Self-publish your writings. Make your own music, or mash up your favorite artists' music. Like films? You can make them and post them.

Alissa Quart, author of Branded: The Buying and Selling of Teenagers, says the walls have fallen between producers and consumers, between "gatekeeper institutions" (media, government, entertainment companies) and those who want access. She calls the new era "perplexing, especially with its questions of status" - as in, who is the authority here? - "as well as issues of taste, what's good, and issues of intellectual property."

Master or slave?

So is "You" king? Does the individual user have more or less control today? Christopher Simpson, professor of communication at American University, says, "Yes, today people have unprecedented ability to create and publish. But that's not the same thing as control."

Control is the subject of a war being waged beneath the surface of the Web. "There's growing concern," Simpson says, "about the ability of corporate or governmental agencies to collect the electronic dandruff we leave whenever we use the Web - and assemble it into portraits of us, our buying patterns, our political lives, our habits, our families - in ways over which we have little or no control."

Chris Bowers, campaign director for the website Daily Kos, says, "Clicks matter. Every time you use Google, Bing, or Yahoo, and click on a search result, that will influence what those search engines show you the next search you do. You build up a pattern, a profile." Or, as Simpson puts it: "The Internet is its own universe of communication - but it's also the most powerful surveillance tool the world has ever known."

As the decade ends, vast powers clash over control of information. The WikiLeaks affair is being called "the first great cyber war." And the FCC's Dec. 21 "Net neutrality" ruling joins a long battle over access to the Web. Simpson calls it "an emerging arms race."

What a first decade for the 21st century. The decade to come will see a world in which we really do live on the Internet.

Contact staff writer John Timpane at 215-854-4406, jt@phillynews.com, or twitter.com/jtimpane.