March 2006: Employees at a podcast specialist, including Jack Dorsey, Biz Stone and Evan Williams, develop a micro-blogging technology they call Twitter. In April 2007, with its popularity rocketing, Dorsey becomes the first chief executive of a Twitter Inc spin-off company.
September 2007: As traffic builds rapidly, the race also begins to monetise the service. In the summer, Twitter buys the search engine Summize for an undisclosed sum and, in September, it launches Twittad to sell advertising on users' online homepages. More importantly, however, a New York Times journalist, Matt Richtel, vows to demonstrate the artistic potential of the service by publishing his novel on Twitter - 140 characters at a time.
Early Nov 2008: Twitter officially attains its majority as a real-world phenomenon when Barack Obama, who'd used Twitter as a key part of his arsenal of digital campaigning devices when he won the Democratic nomination, uses the same array of techniques to help secure the presidency. Its usefulness in a crisis is underlined during the Mumbai terrorist attacks when witnesses cumulatively post tweets at more than 15 per second.
Late Nov 2008: Twitter rejects a $500 million bid by Facebook to acquire the company, the main stumbling block being disagreement over the price of Facebook's stock being offered instead of cash. A canny move given what was about to happen to stock valuations. Twitter sources point out that registration has been growing at a rate of 600 per cent over the previous 12 months - now it wants to find its own way to commercialise that growth.
January 2009: But its credibility suffers in the UK when it's revealed to be popular with the likes of Alan Carr, Boris Johnson and Stephen Fry. Its cutting-edge image is further damaged when the company also announced that UK activity has grown 974 per cent year on year.
Fast forward ...
July 2009: Twitter has been growing at a phenomenal rate, but with corporate suitors circling, the Twitter boss, Williams (who'd succeeded Dorsey in 2008), needs to drive growth even faster - and he targets older demographics as having the greatest as-yet-untapped potential. So there's much excitement when he unveils a new UK marketing campaign, with endorsees including Michael Parkinson, Des Lynam, June Whitfield and Jimmy Tarbuck.