• Early years
    Dorsey gets his taste of real-time services
    Using a Macintosh computer his dad bought for him, a teenage Dorsey uses police scanner data to write a graphics program that illustrates vehicles as they move around his home city of St. Louis. Later, at 17 years old, Dorsey begins dabbling in bike messenger dispatching software.
  • The college years
    Dorsey hacks a bike messenger dispatching service
    Dorsey, a bored junior at University of Missouri at Rolla, hacks into New York-based Dispatch Management Services, a bike messenger dispatching company. He points out the security flaw to the company’s chairman, Greg Kidd, who is impressed with Dorsey and asks him to drop out and move to New York to work with him. Dorsey takes the job, and later enrolls in NYU to appease his parents.
  • 1999
    Dorsey drops out of NYU and moves to California
    Inspired by their work in New York, Dorsey and Kidd team up and move to Oakland, where they co-found a startup focusing on dispatching taxis, couriers, and emergency services over the internet.
  • 2000
  • 2000
    Dorsey sketches out Twttr
    Inspired by early blogging pioneer LiveJournal, Dorsey conceives of a more live LiveJournal while living in Oakland, a service in which posts appeared in real-time and “from the road.” The idea was “akin to updating your AIM status from wherever you are, and sharing it,” he later wrote in a Flickr caption attached to an early sketch of what would become the Twitter interface. The idea stuck with Dorsey, weaving its way into his dispatch work.
  • 2002
    Dorsey, defeated, moves back to St. Louis
    After wrangling with board members, Dorsey is fired from the dispatch company, which later went under in the dot-com bust, and moves back home. In his idle time, he comes up with the idea for a chair-massage service for programmers to help with their wrist aches, but ultimately drops the idea. He also gets a nose ring and an S-shaped tattoo.
  • 2005
    Dorsey moves back to San Francisco
    Desperate to get back to programming, Dorsey agrees to look after Kidd’s children in exchange for housing and lives in a shed on the Berkeley–Oakland border. He finds a short-term coding gig on Craigslist to create a more secure online ticketing system for the ferry company that carries tourists to Alcatraz Island.
  • Later in 2005
    Evan Williams hires Dorsey to work at Odeo
    Dorsey bumps into established tech entrepreneur Evan Williams, who sold Blogger to Google, at Caffe Centro in the South Park section of San Francisco. Having recently been turned down for a job at shoe store, Dorsey applies to Williams’ podcasting startup Odeo. Williams, in need of programmers, agrees to hire Dorsey as a low-level coder. (Image Credit: Joi Ito/Flickr)
  • 2006
    Creation of Twttr (according to Jack)
    After Apple’s introduction of podcasts in the new version of iTunes, Odeo’s business model was in tatters. Williams decides to hold a hackathon to come up with a new direction for the company. Dorsey, still enthralled by the idea of real-time networks and communication platforms, decides to marry SMS, the messaging network for cellphones, with a website that would bounce people’s status updates at one another. The idea eventually picks up steam, with help from Odeo co-founder Noah Glass, and Dorsey and German programmer Florian Weber build out the prototype in two weeks. Glass picks the name Twitter out of the dictionary, but Odeo execs stylize it as twittr to piggyback off the success of Flickr.
  • 2006
    Creation of Twttr (according to Noah Glass)
    In an alternative telling of who came up with the idea of Twitter, Glass recalls sitting in his parked car with Dorsey at 2AM. while the two sobered up after a night of drinking. Glass is listening to Dorsey’s real-time status updating pitch, something Glass had heard before, and Dorsey expresses disappointment that the Odeo higher-ups don’t seem to realize its potential. In an “epiphany,” Glass comes up with an different version of the idea in which users are focused less on updating the world about themselves and more interested in communicating with one another. However, Twitter won’t gain this function for many more months, and only at the suggestion of an early user who intuitively posted a tweet with the @ symbol.
  • March 21st, 2006
    Dorsey sends out the first public tweet
    At 12:50PM on March 21st, 2006, Dorsey sends out the first public tweet: “just setting up my twttr.” Around 12 minutes later, he adds, “inviting coworkers.” Twttr launches to the public on July 15th, 2006, and is renamed later that year to Twitter. Glass, who was dealing with the dissolution of his marriage, becomes unpredictable in public-speaking events and has routine outbursts at fellow employees over the direction of the product, leading Williams to fire him. Contention still exists over whether Dorsey was involved in the decision to oust Glass, whose Twitter bio to this day reads, “I started this.”
  • 2007
    Dorsey becomes CEO of Twitter (for the first time)
    Twitter begins amassing users at an accelerated pace after it goes viral at the South by Southwest festival in March. Obvious Corporation, the holding company created by Williams, Dorsey, and Odeo executive Biz Stone to acquire Odeo, spins off Twitter as its own startup with Dorsey as its CEO a month later. That summer, Twitter receives a $5 million Series A investment round.
  • 2008
    Williams and the board force Dorsey out
    Following a second funding round and increasing public attention, Williams and prominent board member Fred Wilson come to the conclusion Dorsey is unfit to lead the company. The board cites Dorsey’s inability to solve a persistent outage issue that is causing the service to crash routinely, the lack of any type of backup for the entire Twitter system, and Dorsey’s tendency to leave work early to attend fashion design and yoga classes. Williams delivers to Dorsey the now-famous line, “You can either be a dressmaker or the CEO of Twitter. You can’t be both.” In October, Williams helps the board push Dorsey out and takes the reins as CEO. Dorsey stays on as chairman of the board.
  • 2009
    Dorsey founds Square
    Dorsey gets the idea for a mobile-payment company when his friend from St. Louis, Jim McKelvey, is unable to sell his glass faucets for $2,000 because he has no way to accept credit cards. Dorsey and McKelvey go in on the idea of a company that would develop a mobile credit card reader, calling it Square after the phrase “squaring up” and in reference to the small, square-shaped readers that plugged into the headphone jacks of smartphones.
  • 2010
    Dorsey begins emulating Steve Jobs
    Now into his second leadership stint at a up-and-coming tech startup, Dorsey begins dressing and speaking like the late Apple co-founder Steve Jobs. The emulation draws criticism of Dorsey, who begins altering versions of the Twitter origin story in public interviews and causes public relations problems for Williams and the Twitter board. Dorsey also sows discontent within the board by convincing new board member and investor Peter Fenton that Williams had sleighted Dorsey during the CEO handoff.
  • 2011
    Dorsey rejoins Twitter after Williams’ exit
    Thanks in part to Dorsey’s efforts to undermine Twitter’s leadership, the company’s board replaces Williams with then-COO Dick Costolo in October 2010, citing Williams’ inability to manage the site’s growth, increase investor returns, and build out a more experienced executive team. Six months later, Dorsey rejoins Twitter as executive chairman with a focus on product development. Dorsey begins splitting his time between Twitter and Square.
  • November 2013
    Twitter goes public and Dorsey becomes a billionaire
    Dorsey begins scaling back his involvement with Twitter, which prepares for its initial public offering. At an opening price of $26 a share, Twitter’s IPO gives the company a valuation of $31 billion. Dorsey’s 5 percent stake in the company is now worth $1.05 billion. In February 2014, Twitter announces its first quarterly earnings results, indicating a $511 million net loss for the fourth quarter in 2013. (Image Credit: Andrew Burton/Getty Images)
  • October 5th, 2015
    Dorsey becomes the CEO of Twitter — again
    After years of uncertain growth, a slumping share price, and an inability to refine Twitter’s long-term vision, Costolo resigns from his CEO role at Twitter in July. Dorsey steps back in as interim CEO. After a three-month-long search by a committee that included Williams, Dorsey is named the permanent CEO of Twitter in October. He will continue to split his time between Twitter and Square, which is now a multibillion-dollar company preparing for an IPO later this year. (Image Credit: Bill Pugliano/Getty Images)