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September 11, 2026Short & citedBlog
Civic Viewpoint.
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How It Works • Social Media

Jack Dorsey

Jack Dorsey is an American technology entrepreneur and software developer best known as a co-founder of Twitter, now known as X, and Block, formerly Square.

Updated September 11, 20261 min readCited sources

Jack Dorsey is an American technology entrepreneur best known for co-founding Twitter (now X) and Block (formerly Square). He has also championed decentralized communication projects like Bluesky and Bitchat.

What it is

Jack Dorsey, born November 19, 1976, in St. Louis, Missouri, is a software developer and entrepreneur. He co-founded Twitter in 2006, helping create a major social media platform, and later founded Square, a digital payments company that rebranded as Block in 2021.

Key details

Dorsey served as Twitter's CEO in two separate periods before stepping down in 2021. In 2025, he unveiled Bitchat, a decentralized messaging app using Bluetooth mesh networking. He has also been involved with Bluesky, a microblogging initiative.

Why it matters

Dorsey's work has shaped social media and digital payments globally, including in Canada. His recent focus on decentralized tools reflects a shift toward alternative communication infrastructure, which could impact how Canadians connect and transact online.

In short

  • Co-founded Twitter in 2006 and Square (now Block) in 2009.
  • Stepped down as Twitter CEO in 2021.
  • Unveiled Bitchat, a decentralized messaging app, in 2025.
  • Promotes decentralized internet and communication projects.
Canadian angle

Dorsey’s companies and platforms are widely used in Canada, including social media services and digital payment tools that affect Canadian users, businesses, and creators.

Quick questions

Who is Jack Dorsey?
Jack Dorsey is an American entrepreneur who co-founded Twitter and Block, and is involved in decentralized tech projects.
What companies did Jack Dorsey co-found?
He co-founded Twitter (now X) and Square (now Block).
What is Bitchat?
Bitchat is a decentralized messaging app using Bluetooth mesh networking, unveiled by Dorsey in 2025.

Sources

  1. Britannica — https://www.britannica.com/money/Jack-Dorsey
    Supports: Birth date; birthplace; co-founding Twitter; role in Square/Block; Bitchat mention
  2. Wikipedia — https://en.wikipedia.org/wiki/Jack_Dorsey
    Supports: Full name; co-founding Twitter, Block, and Bluesky
  3. Biography.com — https://www.biography.com/business-leaders/jack-dorsey
    Supports: Birth date; birthplace; founding Twitter and Square; career overview
  4. Business Insider — https://www.businessinsider.com/jack-dorsey-twitter-creator-billionaire
    Supports: Twitter leadership timeline; Square/Block rebrand; resignation as Twitter CEO
  5. All American Speakers — https://www.allamericanspeakers.com/celebritytalentbios/Jack+Dorsey/384063
    Supports: Bluesky association; Bitcoin-related advocacy; Bitchat mention