Back in the mid-noughties, an era so distant in web time that Facebook was still in nappies, Twitter creator Jack Dorsey tweeted the first tweet: 'Just setting up my twttr'. The public service began in July 2006, growing out of an internal communications prototype built by Dorsey for his then employer. Within a year, users were posting 60,000 140 character-or-fewer tweets a day, and Twitter was suddenly one of the hottest start-ups in web history. Dorsey and co-founders Ev Williams and Biz Stone were besieged by eager investors.
It has been through no fewer than six rounds of funding, raising around $350m in the process. Not bad for a business which had no visible revenue stream until it introduced 'promoted tweets' advertising last year and which has yet, as far as anyone knows, to make a profit. Based in San Francisco (where else?), its backers include all the big-name west coast VCs: Benchmark, Kleiner Perkins, Union Square - plus Silicon Valley royalty such as Marc Andreessen, Chris Sacca and Jeff Bezos.
Who's the boss?
Twitter has had more new front men than a superannuated rock band. Jack Dorsey himself was CEO until late 2008 when Ev Williams took over. Then last October, Williams stood down, ostensibly to work on product strategy, and was replaced by current CEO Dick Costolo. Both Williams and Costolo pursued a more commercial strategy than Dorsey, including introducing those aforementioned ads. Just to tangle the web even further, Dorsey announced in March that he was returning as executive chairman.
The secret formula?
Sending and receiving short, timely messages in answer to the question - what are you doing now? Whether by accident or design, Dorsey - once a writer of despatching software for taxi firms - hit on something entirely new. Now everyone from Stephen Fry to John Prescott, Piers Morgan to Barack Obama is telling the world what they're up to. Twitter's USP is its brevity, so even if tweets aren't always interesting, they are at least short.
For all the scoffing about celebs who 'over-share' what they had for breakfast, Twitter has become an agent for democratic change. Tweeting activists helped bring protests in Iran to international attention last year and to topple Egyptian dictator Hosni Mubarak this year.
The Fail Whale. Or the fact that, for a service that is all about spreading the word, Twitter is tight-lipped about its progress. Does the lack of official revenue and user numbers hint at a dark cloud gathering just beyond Twitter's sunny horizons?
Users: 200 million (estimated)
Annual turnover: £100m (estimated)