What Happened on March 21st

 
Jack Dorsey Sends First Tweet

The origins of Twitter came out of a brainstorming session at the podcasting company Odeo. The initial concept was to share short messages via SMS text messaging with a small group. Jack Dorsey was the primary designer of what was then code-named “twttr” and sent the first message at 9:50am on March 21st, 2006 - "just setting up my twttr." Twitter would be released to the public that July and found its first major success at the South by Southwest Interactive conference in 2007, shortly after it had been spun-off as its own company, Twitter, Inc.