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Twitter: The tweet that shook the world
Politicians have been excited by the new way of connecting with the public, including Obama, whose staff used Twitter during last year's election, and a steady stream of MPs, congressmen, senators and other influential individuals.
When President Barack Obama wasn't concerned with swatting flies or wrestling with Congress last week, he had something else on his mind. Despite the political wildfire spreading in Iran, State Department officials were hamstrung by America's difficult relationship with Tehran: they wanted a way to influence events on the ground without getting involved in them. And so they turned to the internet.
Their unexpected source, though, was not Iran's vast army of political bloggers or even the web providers blocked by the country's censorious government. Instead, they went to American online messaging service Twitter, the social network that had swiftly become a central source of information with blow-by-blow updates about the post-election protests.
Hearing the news that engineers at the Californian company were planning to take the website offline to perform some maintenance, officials in Washington made what perhaps marks the oddest political phone call seen since Dr Strangelove.
Their message to Twitter? "Don't stop."
"It's humbling to think that our two-year old company could be playing such a globally meaningful role that state officials find their way toward highlighting our significance," said Biz Stone, one of the company's founders the next day.
The site undoubtedly played a vital role in spreading the story from inside Iran to the outside world, as thousands of web users and mobile phone addicts passed on messages and pictures documenting events on the ground.
It is easy to overestimate Twitter's value inside Iran, where word of mouth, phone calls and text messages were almost certainly more important in helping to organise rallies. But its influence in making the story global was very real.
All of this attention marked the latest high point in Twitter's dizzying ascent, a rapid rise that has seen its crew of geeks find themselves at the heart of geopolitics more by accident than design.
Three years ago, the company's founders were toiling away on a different internet project, an interesting but ultimately unpromising podcasting company called Odeo. Programmer Jack Dorsey showed his colleagues an idea for a simple website that let people update their activities and whereabouts by mobile phone. They liked it, built a prototype and Twitter was born.
Long before it became a high-powered political tool, however, it began simply as a way for geeks to tell each other what they were doing online.
It allows each user to send a short update on their current activity to a selected group of friends from a computer or mobile phone. Restrained by text message technology to a limit of just 140 characters, users answered the question: "What are you doing?" in as straightforward or creative a way as they chose.
What started off as a side project soon became the main event; the team switched from Odeo and the third co-founder, Evan Williams, used the proceeds from his previous business (Blogger.com, which he sold to Google in 2003 for several million dollars) to fund Twitter's early development. Then, it was known as Twttr, though that name, displaying the disemvowelled grammar that became a hallmark of trendy web companies in recent years, was swiftly ditched in favour of a more mainstream-friendly version.
Cheered on by adoring crowds in Silicon Valley, the site blossomed, turning into a sort of internet chat-room as millions of people swapped messages.
Importantly, it was boosted by the presence of celebrities: famous British faces like Stephen Fry, Jonathan Ross and Philip Schofield, as well as American names like Britney Spears, rapper 50 Cent and basketball star Shaquille O'Neal.
Because users choose whose messages they want to see on their Twitter home page, these famous names could actually interact with their fans - albeit in a limited way.
Unsurprisingly for a trio of archetypal San Francisco geeks, its creators have struggled with their newfound celebrity pull. "The level of attention has been surprising," said Williams, with typical understatement.
And yet they court it all the same: Oprah Winfrey invited a bashful Williams on to her show in April for a special segment dedicated to the service, while Stone looked slightly overwhelmed during an appearance on the popular spoof chatshow hosted by comedian Stephen Colbert.
"My guest tonight is the co-founder of Twitter - I'll ask him about every mundane moment of his life," quipped Colbert.
Except it is that mundanity, in part, that has helped push Twitter from a nerdy experiment to a genuine phenomenon: it is easy to use, but vast in its scope.
Plenty of detractors have gnashed their teeth along the way: they despise its addictive immediacy, the hype that has accompanied its rise or, more often, they complain that it improperly elevates the inner thoughts of those who trade in banalities and mindlessness. Some attack its inherent unreliability (though since they get to choose precisely whose messages to read, the question seems moot), while others decry its growing power online.
Worse still, then, that it has been embraced by the celebrities who often represent the worst strands of our vacuous and fame-seeking modern culture. But for every Britney Spears, Twitter has also shown the surprising ability to inhabit a geopolitical world.
Clay Shirky, a professor at New York University renowned for his analysis of the way people interact online, has described the attraction in glowing terms. "These tools don't get socially interesting until they get technologically boring," he said recently. "It isn't when the shiny new tools start permeating society, it's when everyone can take them for granted."
Indeed, its impact was so powerful that Shirky has since called Iran "the big one ... the first revolution that has been catapulted on to a global stage and transformed by social media".
With lives on the line at Tehran's anti-Ahmadinejad protests, few could mock the inanity of the system, but Iran is just the latest in a series of major events that have been given an extra global witnesses thanks to Twitter.
Early last year, the first reports of the earthquake in China's Sichuan province broke on Twitter, while the end of 2008 saw users document the Mumbai attacks for a global audience before the news networks had got on to the story. The first images of the US Airways craft that crash-landed in New York's Hudson River, meanwhile, prompted the BBC to call it "a classic of the new age of citizen journalism".
As a result, what started as an experiment between a handful of employees has now found itself reaching a strange crossroads where society, technology and politics interact with each other, sometimes with profound effects. And in doing so, Williams, Stone and Dorsey have become the latest in a parade of US technology geeks who have achieved some form of political influence without ever being actively political.
Their predecessors in this include Google's founders, for example, who espouse a "don't be evil" mantra despite the fact that their intentions remain vague and their philanthropy is often tightly linked to the business they started. Microsoft billionaire Bill Gates, meanwhile, has turned his sizable bank account to saving the world, but only after he had spent 20 rapacious years becoming one of the most powerful people in it.
The end result is that Twitter is riding a curve of hype that, for the time being, shows no sign of turning back against it. Celebrity allure, political power and technological smarts have all arrived at the same time.
That is all nothing compared to its reputation on its home turf, where, despite much-heralded internet startups being 10 a penny, Twitter is regarded largely with reverence. Everyone from Google to Apple has reportedly inquired about buying the company, and earlier this year Twitter rejected a $500m takeover bid from Facebook.
By anybody's standards, that is a high price to turn down, but in the face of an almost insatiable appetite from the public, the company's creators believe they have stumbled upon something that is worth substantially more: in prospecting for a way out of the doldrums of their previous business, Williams, Stone and Dorsey instead found gold.
"I've called it social alchemy," said Stone recently. "Take a tweet that you think is meaningless or valueless - like I'm grabbing a beer at the airport. It's of little value, but if somebody gets it in real time ... and they say, 'I'm in the airport and I'll meet Biz for a beer', we've turned that lead into gold."
The Twitter Lowdown
21 March 2006 - opened publicly in July of the same year.
Jack Dorsey (4 April 1977), a programmer from St Louis, Missouri; Biz Stone (10 March 1974), social networking expert from Massachusetts; and Evan Williams (31 March 1972), serial entrepreneur from Nebraska.
Best of times:
Twitter has a recurring role in helping spread news of major events, but it was an appearance on Oprah Winfrey's popular US television show that took it to the masses. The host logged on to the site with a welcome of "HI TWITTERS" - immediately gaining more than 250,000 new fans and sparking a huge growth in the site's user base.
Worst of times:
The site was so unreliable for a period in 2008 that the so-called "fail whale" - a character who appears whenever the site is overloaded - became a cult figure with its own online fan club.
Others say: "It is a magnificent way of cutting out the press. I'm getting new tweets all the time and some of them are very amusing and some of them are rather silly, but most of them are entirely charming." Stephen Fry, one of Twitter's most popular and enthusiastic users
They say: "It distills a lot of what makes the internet exciting into a really simple form." Evan Williams in a TV interview.