He removed his nose ring in an attempt to look the part of a mature Silicon Valley executive, though he kept his boyish, mop-like haircut and abstract, forearm-length tattoo whose shape represented, among other things, the human clavicle bone. On March 21, 2006, Jack Dorsey posted the world's first tweet: 'just setting up my twttr.' Dorsey was named the company's chief executive officer. Within two weeks, Dorsey had built a simple site where users could instantly post short messages of 140 characters or less, known in Twitter parlance as 'tweets.' Dorsey, Stone and Odeo co-founder Evan Williams started a new company, called Obvious, which later evolved into Twitter.
'He came to us with this idea: 'What if you could share your status with all your friends really easily, so they know what you're doing?'' said Biz Stone, a former Odeo executive.
Dorsey approached a now-defunct Silicon Valley company called Odeo to pitch the concept.
