Twitter CEO's journey from microblogging pioneer to billionaire

Jack Dorsey on Monday stepped down as the chief executive officer of Twitter Inc, the social media firm he helped found in 2006 and steered through a high-profile hack and the controversial banning of former US President Donald Trump.

Dorsey, who also helms fintech firm Square Inc, will be succeeded by Chief Technology Officer Parag Agrawal.

Here is a timeline of milestones in Dorsey tenure at Twitter:

2006 "just setting up my twttr".

2008: Co-founder Evan Williams took over as CEO after the board pushed Dorsey out. Dorsey assumed the role of chairman.

2013: Twitter went public at a valuation of $31 billion.

2015: Dorsey returned as CEO after Dick Costolo stepped down.

2017: A Twitter employee on his last day deactivated then US President Donald Trump's account which was restored 11 minutes later.

2018: Twitter increased the character limit of tweets to 280 from 140, sparking a mixed reaction in twitterverse.

2020: Activist hedge fund Elliott Management pushed for changes, including the removal of Dorsey as CEO.

2020: Twitter reached an agreement with Elliott to add three new directors for letting Dorsey stay on as CEO.

2021: In the wake of the riots at the Capitol, Twitter permanently suspended Trump's account, with the company citing a risk of further incitement of violence.

2021: Twitter outlined plans in February to attain at least $7.5 billion in annual revenue and 315 million monetizable daily active users, or those who see ads, by the end of 2023.

2021: In March, Dorsey sold his first tweet as a non-fungible token (NFT) - a kind of unique digital asset - for just over $2.9 million.

2021: Former US President Donald Trump in July filed lawsuits against Twitter, Facebook Inc and Alphabet Inc's Google, as well as their chief executives, alleging they unlawfully silence conservative viewpoints.

2021: The company said it had 211 million average monetizable daily active users, as of the three months ended Sept. 30.

2021: Dorsey's net worth is $11.8 billion as of November 29, according to Forbes.